All of a sudden he pushed me out of his life and became so cold... Please tell me what to do? What happened?

You don't know the man. You never did know him. He was holding something back from you and your daughter, and he probably realized that someday you would find out that he isn't who he pretended to be. He may not have done it on purpose, he may have been trying to deceive himself too, but it isn't something you can fix. All the understanding in the world is only going to enable him to hurt you and, worse, hurt your daughter again. Shore up your defenses, girl, and step back from the edge. If you want to wait on the man, do it from a distance, for your daughter's sake if not your own.