@Is love enough,
Wow. I can't believe people are telling you to stay with him.
He's going to the movies with his ex? What?
How easy would it be for her to just start kissing him? You think he would just say... Nahhh... can't do that anymore? He's a guy. We have hormones... there is no way you can trust him if he's doing that. If you do trust him, I would love to sell you a bridge. You're being beyond guillible.
If you stay with him... don't even have the nerve to act surprised when he tells you his ex is pregnant with his baby. Of course, he'll probably be telling you on Maury or Jerry, so it should be a little easier to see coming.
I'm not trying to be mean, but wake up.