My boyfriend is talking to a girl he used to love, and I don't know if I should be worried about it?

[easy does it]

Sounds like your in a tough situation. The only thing I can offer is to lay it out on the table and just say that you have been going through his messages. He may not react positively, but he's been honest with you (mostly) and I don't think keeping this a secret is going to be good for either of you.

Maybe you should ask him exactly why it is he won't talk about past relationships. It's obviously something that can't be ignored ad hole it may be a touchy subject it's better to have at it than to push it under the rug.

Good luck