Why is it that we as people fall in Love with someone and then spend the rest of your life trying to change th?

spend the rest of there life trying to make them into something else,where as if you were to truly be open and honest when you meet someone whom you have feelings for and not try and be who you think the other person wants it would save everyone alot of heartache I speak from experience because I am as guilty as the next person. I have tryed to make myself into someone I was not for a man I felt I loved and all it did was drive me up the wall. So if you agree with me I would love to hear your thoughts. As we all know this is why people Divorce is because we present ourselves as something we are not or vice versus. The other reason I believe is that we grow and change into a different person by friends or other reasons. Life is a big mystery and by the time we think we have it figured out we are at that point when our life is half over. I feel this to be sad.