Many, many cloistered religious sisters take vows because they don't want to be mothers or wives. They know they are not suited.
It seems from how you have expressed yourself that you don't understand the concept of a religious vocation. Nobody should enter a convent for the reason that they don't desire to marry and have children.
As for "they are not suited" (to have children), God made woman for the express purpose of making man happy (being his helpmate throughout the length of his or her life) and bearing his children.
But there is a life which serves the purpose of demonstrating to the rest of us who are not so chosen, that there is a higher life - the spiritual life where one sacrifices God's wonderful plans of Marriage, for a higher one. A woman becomes a religious, because she is CALLED by Jesus to be His Spouse. She has children, in the spritual sense. She is not a natural mother, but a supernatural mother.
I never took the fact that I did not desire to be married (until I was 30) as a sign of a vocation to the religious life. I was just never called to it. You can't just invite yourself.
On the other hand my mother had a great desire to be a contemplative nun. She worked voluntarily in a nursing home run by nuns. One of the old people told her - without being asked or told, the comment came completely out of the blue - that she was not meant to enter. Shortly after that, she met my father and they lived happily ever after...
I don't know if she has a "rancid soul". There's the possibility that I have one too.
I doubt very much from what you are saying and where you are sitting, that you have a rancid soul. I would say however that you have yet found your niche but with prayer and searching you will. I hope you will find it and be very happy.