I hear your sadness coming through. Fact remains, you were very successful today. You did good. When you get back to yourself, you'll be proud.
Yes, let him go. It's true, it's only love if he comes back of his own volition. And really, don't take it so personally. That man you dealt with today is not the man you married. Can't say why he changed. Only know that he changed. Not the same man. Let him go.
