Ex-boyfriend help please?

Okay so my ex broke up with me about 2 months ago for reasons unknown. We were about to celebrate our 1 year and then he said he just didn't know if he loved me anymore unexpectedly. After the breakup he said he still wanted to remain friends with me and didn't want it to be "as if I never knew you". We have 3 cles together in college so we see each other pretty often. He always comes and sits down next to me, he tags along when my friend and I ditch cl, and he even came to a high school party that I invited him too. We had been trying the friend thing for a while, and although it was really hard for me, I did it because he said that that's what he wanted and also because I still wanted him in my life somehow, even if it wasn't as my boyfriend. So a week ago my mom finally talked to him about the breakup and he told her "Its because of the predicament that we're in (being in 3 cles together) that I even speak to her. I'm trying to make the best of a bad situation. I just want this semester to be over so that I can go my separate way. And in the future if I see her in ping, I MAY say something to her, but I get to decide if I want to or not." I was COMPLETELY hurt, I couldn't believe that the person I loved and who loved me not to long ago, would say something like that about me. He broke up with me, and it's HIM that doesn't wanna speak to me again? I'm sooo confused. And he puts himself into the predicaments that he says he hates so much, so I really don't understand. The day after he told my mother what he said, he came into cl and started talking to me, and I rolled my eyes and wouldn't respond. Now he no longer speaks to me and anytime I walk past him he either closes his eyes or looks in the other direction so that he doesn't even have to look at me. And now even though we NEVER speak to each other, he always comes and sits down next to me in cl, even when I change where I sit from day to day. Also yesterday he saw me walking with a guy and we made eye-contact from afar, but when he walked pass us, he held his head up and looked STRAIGHT ahead without once looking in our direction. Can someone please help me understand him!?