Mary
Mary is described in the Bible as being ‘highly favoured ‘of God as He was going to use her to make the body His son was going to inhabit. God supernaturally started the conception of Jesus and then used the natural processes in Mary’s body to grow this child till it was born. Mary did little, only what was natural to any gestation and birth.
She is hardly mentioned after Jesus grew up and started ministering and when she is mentioned she is either trying to stop Him ministering or as an observer to what is happening (Cana and Calvary).
Why has the Catholic church attributed to Mary so much?  There  appears no basis, in The Bible, for these attributions .
The way the Catholic church has treated Mary is such a serious subject that some things will be examined in a more detailed way.
The problem is that most of what Catholics attribute to Mary is not in the Bible.
Because most of what is attributed to Mary is not in the Bible it cannot be doctrine and needs to be examined in terms of the second Test and treated (if they pass) as a belief of The Catholic Church that cannot be criticised by others or imposed on others by the Catholic Church.
Mother of God
This title is not found in The Bible so must be man made.  The Bible only ever calls Mary the mother of Jesus and not of God  so any other title has to be made up by a person and is not from God.
It cannot mean she gave life to God or this would make her equal or greater than God which would be idolatry and would fail the second test.  If it means anything more than God used her body for His purposes Then it is idolatry.
Mother of The Church
Mary cannot be the Mother of the Body of Christ as it a spiritual thing and not physical as The Body existed before she was born.  She also cannot be the mother of The Catholic Church as she had nothing to do wit its formation.  Jesus establishes His church and she also has no part in this.
Remember that The Body consists of all those in heaven, those on earth and for a time, those in the Old Testament or earlier who waited for Jesus to come so they could go to heaven where they are now.
As the church is not The Body it does not matter what title is given to her as long as it does not displace Jesus in any way or contravene what The Bible teaches.
Mary’s role in perfecting The Church
Jesus is the author and finisher of our faith and Mary has no role in this.  This role of perfecting the church (The Bod of christ) is not in The Bible and is against what The Bible Teaches so it fails The first test and is thus doctrinally unsound.  As it fails the first test it must be examined under the second test.  It fails this test as it is idolatry and removes from Jesus things that are His alone.
Her ‘spiritual’ motherhood.
Para 501 of the Catholic Catechism states that Jesus is Mary’s only son.  This incorrect as other siblings are mentioned in the New Testament.
Her assumption
This refers to Mary being free from sin, being taken into Heaven and made queen of heaven by Jesus!  This is doctrinally unsound. We are Told that all have sinned (Rom. 3:23). There is also no Biblical evidence for her being caught up into heaven and so this is also doctrinally unsound.
There are also no witnesses to this so called assumption and this doctrine was not a part of early church doctrine for hundreds of years.
There are also other problems with the assumptions:

There is no prophecy in regard to it.  It was decreed by a man, a pope. There is no prophecy to match this event there is for the virgin birth and resurrection of Jesus. Surely a significant event as this would have been prophesied in the Bible.
It was not in the early Church for hundreds of years.
It gives glory to Mary and not Jesus.  
It goes against the fact we are given a resurrection body to replace this body that is defiled
Nothing defiled can enter the kingdom of God, so it is impossible for this body to go to heaven.  She was still in a defiled body when supposedly assumpted and could not enter heaven

Queen of heaven.
Jesus is King of heaven, For her to be Queen she would have to be His wife,  This means she wold have had to marry her son Jesus.  This idea alone is abhorrent.  Perhaps she cold have been under Jesus as a subordinate queen but as her queenship in heaven is not mentioned in  The Bible all one can do is conjecture as how this position has been arrived at for her.
Her ‘immaculate’ conception.
This states Mary was not ‘polluted’ by sin or born in iniquity at her birth. The Bible says we are all conceived in iniquity so this concept contravenes The Bible and is doctrinally unsound.
Everyone is born without an understanding of sin and until they understand right from wrong they cannot knowingly commit sin.  So there is nothing special about Mary not having sin when she was born. In regard to iniquity, God said the following as a principle in His creation:

Exo 34:7  Keeping mercy for thousands, forgiving iniquity and transgression and sin, and that will by no means clear the guilty; visiting the iniquity of the fathers upon the children, and upon the children’s children, unto the third and to the fourth generation.

Mary could not escape being born in an environment of iniquity.  So The Bible says she was not free from iniquity at birth but was free from sin at birth as she did not know what it is to commit it just like everyone else who is born so there is nothing special about Mary’s conception.
Note that iniquity comes through the father (Ex 34:7) because of the sin of Adam.  The Father of Jesus was sinless so there was no iniquity in the birth of Jesus unlike everyone else (including Mary) who has ever been born.
Some other titles
Mary is also quoted as:

Our example of Holiness
Our example of Obedient faith
The one showing the way to the Father (in contravention of Jn 14: 6)

We are told to look to Jesus for these things and no one else.  These attributions fail the second test by displacing Jesus as Lord.  They also fail the first test and are doctrinally unsound because they declare Mary does these things when The Bible says Jesus is the one doing these things!  As these activities ascribed to Mary also fail the parts of the second test they are idolatrous.
Other problems with Mary.

Mary did not have a divine birth like Jesus.
She did not do the work of the kingdom of God: preach, teach, demonstrate it, cast out demons or do miracles
She is basically ignored in the Gospels after the manhood of Jesus is reached and when spoken of is shown in one place trying to stop Jesus doing the work of The Father on earth.
She is not God so cannot do miracles unless Jesus does them for her.  So why does she received the credit for doing them and not Jesus. We are also told The Holy Spirit empowers us and not Mary
In the New Testament, Angels or Jesus proclaimed things to people.  If Mary is telling things to people they would be from Jesus.  So why is she being given credit for them?

Why is so much made of Mary being a virgin.  God did all the work and she had other children after Jesus.
When you pray to Mary for any reason you worship her (because you believe she’s worthy to pray to, which is worship) and she becomes an Idol.  Jesus says the only way to God is through him and gong to another calls Jesus a liar, as it places them before Him and makes them an Idol.
We are also told Jesus is our high Priest who continually intercedes for us.  So why do you go to Mary for something Jesus is already doing.  Jesus is God and knows what to pray for and Mary cannot ask more of him that He is praying already.  Besides, if we need help and do not know what to ask The Holy Spirit has been given to pray for us.
Why do they not worship Jesus who is behind everything Mary is supposed to have done and worship her instead and put her before Jesus in these things.  So that He is not given the recognition for them.  This is perhaps the main reason Mary has become an Idol.  she has displaced Jesus as the source and has become between Jesus and his followers.
The Hail Mary
The first part of it is in The Bible so is not a problem for us.  It is the second part that needs to be examined.
When Mary said this she was making a statement of acceptance and thanksgiving for being chosen to be used to make The body of Jesus.  To turn it into a prayer can only be for worship, especially when the next part of the prayer asks her to pray for us as if she had a special status so that her prayer was mot effective than ours.  This is a form of worship if we consider her prayers are more effective than ours.
There is the problem though that it is a prayer to Mary and that automatically means worship of her and is idolatry.  It is worship because you think she is worthy to pray too and that displaces Jesus.
In regard to the second half of this prayer:

Test one.  Is it in the Bible?  No!
Test Two.
Part (a): Does it take Glory from Jesus?  Yes as Mary is honoured and not Jesus and all Glory belongs to God.!
Part (b):  Does it break the law of love?  Yes as you are praying to another instead of Jesus and who is replacing your love for Jesus in your heart (whether you realise it or not)
Part (c):  Does it lead to idolatry?  Yes in view of (a) &( b)  above!

Accordingly it is not  practice that can be recommended and is even dangerous.
The Rosary
Applying the tests on the Rosary and its derivatives like Perpetual Novenas or Novenas the following is arrived at

Test one.  It is in the Bible?  No!
Test two
Part (a): Does it take Glory from Jesus? Yes! as the main focus of prayer is to Mary.
Part (b): Does it take your focus off Jesus?  Yes! As the main focus of prayer is to Mary.  
Part (c): Does it lead to idolatry?  Yes!

Accordingly it fails as a practice to be recommended
So how should we relate to Mary?
Worship
The moment you pray to Mary you or ask her to intercede for you with God (Jesus) you are worshipping her because you declare she is worthy to pray to or to intercede for you with God.  This displaces Jesus.  This means you can treat Mary as a friend in heaven and not anything else or it becomes idolatry.
She can be your friend in heaven but it will be one sided relationship.  Better concentrate on friends on earth who at least can be seen by you and interact with you.
Can she be your example of holiness?
We are not told how she lived the Christian life so cannot be an example for that.   She is not even a good example of how to live as a good Catholic should not ever having done any of the practices a normal Catholic does.:

She never went to confession
Went to communion and had the host
Never said The Hail Mary’s or rosary
Is never recorded as being baptised in Jesus

She is an example of someone who obeyed God and that is all, as she observed The Mosaic Law originally and probably observed the lifestyle flowing from the death of Jesus after His Resurrection but we are not told anything of her after the death of Jesus except she was with the Apostles waiting for Pentecost.
So really, Mary is not a good person to have as a friend or to follow as an example  of living The Christian life.