Why does he care if I'm talking to other guys?

Anonymous
Long story short as possible.

I'm have been messing with a guy for a few years about 3. We were both in other relationships that fell apart a few months ago. For a few weeks everything was great then about a month ago he came to me and said, I want to tell you something but I kind of don't because I'm not sure you will like it. He told me he met someone that day and they were going to hang out and see where it went. Here we are a month later they are dating. I will admit I am in love with him and have been for a long time. He says he cares about me I am his bff and he can't imagine life without me but doesn't want to be with me in a relationship right now partly because I remind him of his ex. So I have been living my life pulled back from even the friendship because it's painful to see him with her. Last Fri. We both ended up in the same bar. I stayed to myself and my friends and he did the same. The next day we were both at a mutual friends house and he made comments about how I was talking to 3 different guys at the bar and that my ass was sticking out the whole time I was talking to the one. ( I was leaning on the bar in between stools ) soo

My question is if he doesn't want to be with me why does he seem so concerned that I'm talking to other men?
Why does he care if I'm talking to other guys?
3 Opinion