I understand your need for closure. I haven't experienced the same, but I have felt betrayed and cheated out of the love I thought I deserved (parental love).. From dealing with my hurt, both on my own and in therapy, I've learned that we build our sense of self, our identity, in relation to other people. And it can go horribly wrong if the people you're dealing with are dishonest, or mean, or selfish, incapable or unwilling to see you as you truly are and project that image back to you.

What I see happening here is your ex calling you a liar when, in fact, he is. He's also spreading the lie to other people - his current girlfriend, at least. I find his behaviour disgusting! Seriously. I feel for both you and his girlfriend. Does he really think the world works like that - he wants something and thinks it's OK to lie in order to have it, making those closest to him (whom he might even claim to love) live a lie as well. Disgusting!

I think you need to find someone to talk to whom you can trust. Don't label everyone a cheat just because he is. He'll probably never agree to clear your name as it might mean their relationship will suffer, or that he'll lose her. He said sorry for hurting you, but what are his apologies worth since he keeps hurting you by continuing to lie!

You need to find someone who does NOT want to see you hurt. Who'll just listen and let you grieve your loss while helping you be happy again. As for wanting to clear your name, other people can tell you he's the liar. Don't waste your time trying the get the least likely person - him - to admit to it.