Heyyy,

I know the feeling as I was recently in the exact same boat as you just a few short weeks ago.

Instead of thoroughly explaining what we went through (that's what i feel inclined to type here o.O) i'm going to just get to how we handled the situation.

Firstly, I see a relationship as two best friends sharing their life experiences with each other. The best way to do that is through communication. If you can talk about anything with SOMEBODY, it should be this person.

Let him know just how uncomfortable it makes you knowing that he has this "friendship" with this other person and that it's taking it's toll on you emotionally.

A healthy and successful relationship lives and dies not by the sword, but by communication. (I read that somewhere) If he see's your feelings are truly hurt by this friendship with this other person, he'll do the respectul thing and make it stop.

Ask him if the tables were turned, how he might feel. Reassure him that you would never put him in this type of situation (Nobody wants to hurt the person they love) and that you're just looking for an honest answer.

Point out to him that you've read this book (or some or part) and he's not put forth any effort.

If your suspicisions are true, and I sincerely hope that they're not, it's going to take a great effort on both of your parts in order to save what you have. Point that out as well.

I hope that all works out for the best!