Can you help me unravel my latest mistake?

Not a happy post this time. Last year I was dating this guy, which was my best friend before that. He broke up with me, two months before I went to Australia because he was missing things in the relationship. Even though we broke up, we decided to try to stay friends, since we used to be such good friends before. I know that it normally doesn’t work, but I really thought that we could.

Today, almost a year later, we were hanging out as friends. I stayed the night, since I was too drunk and tired to get on the bike, and he was fine with that. The whole evening and today were filled with just hanging and watching movies, which is what we do a lot. 

When I got home, he told me that he couldn’t hang out anymore, since he still loves me and it hurts too much for him. And I do understand that and I don’t want him too hurt because of me, I feel so crappy now. Apparently everytime we hang out since I got back, he felt extremly shitty and I didn’t know it, so I just acted like I normally did with him, which made him feel worse. I feel like such an egoistic and stupid friend that I didn´t noticed it and that I caused him so much pain. Normally I would talk to him about things like this happening, but I can’t do that now obviously. 

I guess I just lose my best friend.