Why did God created women?

This is basically an erronous view that some men think that they should blame women for their own sins. If he, whoever he is, tries to say that this means God doesn't want everyone to come to Him, they obviously he is not a proper theologian as his lack of knowledge of what the scriptures say show such.
God does not cause nor is the source of temptation-
James 1:13-16
Let no man say when he is tempted, I am tempted of God: for God cannot be tempted with evil, neither tempteth he any man: But every man is tempted, when he is drawn away of his own lust, and enticed. Then when lust hath conceived, it bringeth forth sin: and sin, when it is finished, bringeth forth death. Do not err, my beloved brethren.
God wills all to come to Him-
2Peter 3:9
The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.
God's purpose for women as a helper made clear from the beginning-
Ge 2:18,20-22
And the LORD God said, It is not good that the man should be alone; I will make him an help meet for him.
And Adam gave names to all cattle, and to the fowl of the air, and to every beast of the field; but for Adam there was not found an help meet for him. And the LORD God caused a deep sleep to fall upon Adam, and he slept: and he took one of his ribs, and closed up the flesh instead thereof; And the rib, which the LORD God had taken from man, made he a woman, and brought her unto the man.
As you can see, this 'theologian is simply as you put it, backbiting God. I strongly advise that you take nothing from this man as his views are erronous, clearly already having led men astray in blaming women for their own sin.

Thanks for your answer, I have just left a lutheran assembly because they called him a great theologian, and I was wondering if I had done the right thing.

Well I've read a little further into Thomas of Aquinas and he is listed among people who have been reported to have levitated- this levitation I cannot think of any scriptural evidence for which to support such an event as by God, nor am I aware of any occurence in any church or Chrisitan gathering of any size where someone has 'levitated'. But however I do know for certain that levitation is a major part of occultism, frequently occuring within occultic circles and by numerous witches and other magic/k practitioners. This would be further reason not to follow anything by him, even if what some things he writes is true, for those truths can be found elsewhere.
Don't think that you have done a bad thing by leaving, if it's not for you then that is just your decision, not a blasphemous act. My advice would be to find a Holy Spirit-led church that isn't bound up in tradition or saint adoration- because all believers are saints, not just those whom the Vatican chooses to make one. I'm not going to say it will be an easy thing to do, but it will certainly be an experience for you to grow spiritually.

he creats woman because you are lonely so he wants a partner to accompany you to colour your life and give love to you!!

Yes, I think you are right (and Thomas of Aquino totally wrong). We male need to have somebody to live for. The expected remaining length of life for a middle-aged single man is much less than to a married.
If I understand genesis 1:27 right it is the marriage that is intended to be an image of God, not a single male or female alone.

God created woman out of man's rib,why because God made woman to be a man's helper.
and another reason God made woman because he didn't want man to live alone.
tomany today thinks that man fails or fall because of woman..i don't think so.
we all fail and fall into temptation because of our own thoughts .
adam gave into eve because of the choose he made..
today some marriage fall apart because of choose we make.