Yup, two ex boyfriends in particular show up in my dreams. They're almost always sex dreams, btw. And NO, I do hot have any desire or urge in real life to sleep with them or cheat on my husband.
But I am happy to say that I really only had the pleasure of dating really good, honest, sincere and loving people. I think they're probably still that way (except they don't love me and vice versa--totally ok

). I wouldn't mind running into them again (er, after I've lost 20 lbs haha!), without any worry that I'd want to re-engage what we once had.
My father, btw, reconnected with two ex girlfriends from his past when he retired. Guess what? They're AWESOME people! And they're now pretty good friends with my mother, too. Wouldn't you know...
Anyway, don't worry about your musings and wonderings. Take it as a sign of your very excellent taste and fortune in men.