Is this fair? Why is he acting like this?

So me and this guy have history. We both liked each other very much but he wasn't ready for a relationship since he recently got out of one. I was more than understanding to that. Long storry short, we never ended up together but still remained friends. We've always had this strong emotional/physical connection to each other, I was always there for him whenever he needed, we were really close. He has hurt me countless times, but wwe alwaays worked through it and I never turned my back on him. He made mistakes but I put that in the past. He recently got a girlfriend, but still has feelings for me ,he began lying to me as well as her. He would tell me one thing and tell her another.Her and I became friend after they started dating ,her and I ending up having lunch, which lead us to talk. Again, he would tell me many things, things I thought she was awarre of about us but then tell her another so when herr and I spoke and she asked questions, I didn't see the harm in ttelling her because according to him, she knew. I found out that wasn't the case. Now he's upset and doesn't want to talk to me because she's now has trust issues with him, but is that my fault? He lied to both of us. He's being such a jerk to me now and I don't deserve that after all I've done for him. Why is he acting like this?, I know he knows he's wrong.