My ex and I ended things the beginning of October. We were happy together, but things moved way too fast and caused things to crash and burn. At first, we just were taking time apart. Thought we had things back to normal, but apparently not. He ended things, we both took it really hard. He asked to see me on the weekends he was home after that. I saw him two times. He wanted to talk about what happened etc. The last time I saw him, he asked if he could see me the next day. I told him I'd let him know. When I went to let him know the next day I got an email back saying he didn't think we should talk anymore because it's not fair for him to let me move on.
I haven't talked to him since. I've ran into him a couple times and today I passed him at a red light, but that's the extent. From what I hear he met a girl at school, which I assume is a rebound because she is young/immature/ and likes nothing he does. Either way, I can't control it and I've accepted it. After the last time I saw him I thought I had moved on. I didn't think about him or miss him. I was spending time going out and met a few guys. Then one night I suddenly missed him. This was about 3 weeks ago now and it still hasn't gone away.I don't understand why this is suddenly happening because I have no reason to miss him whatsoever.
How do I get past this since obviously nothing I've been doing is helping? I don't want to ruin new relationships with others because I'm hung up over him when I'm trying so hard not to be