Why do lovers hide most of the truth while dating?

I think it is truth what your friends said. my boyfriend don't tell me lots of things about himself and he never tell me about his ex-girlfriend whenwe dating. but he tell me when we are very familar and he also tell me about his history. so when dating, especially first dating, I THINK lovers will hide most things . but they will trust each other when they really fall in love.

I had a guy that pretended to be something he is not. Kept up the lie for a long time. I found out in the end and I dumped him. He never gave a a straight answer as to why he did it. Now I look back and think he's just a complete waste of time.

Well, sometimes we don't like to share too much of ourselves with the people that we date but I think that changes for some people after they decided to be together forever.