Why is it so hard getting over an ex, even when you know they are no good for you?

It's been a week since I broke up with my ex with whom I was extremely incompatible. I don't think he is a bad person, I think we both tried meeting half way, but our differences in what we need and our life style in general were too big to compromise on. I felt like low priority to him and he felt not good enough. The funny thing is we weren't wrong; given his job and family situation, I WAS a low priority. He took our relationship for granted thinking I will be there no matter what and that one day he will be there for me 100% too (after he sorts his life). And I DID make him feel not good enough, because he wasn't. I was settled in in my life; good job, my own place, good income, lovely family, ready for marriage and kids. He was nowhere near it, any of it. And I waited long enough for things in his life to change...
I was absolutely in love with him. And I miss him. But more then I miss him, I wish things were different, I wish he was more stable, I wish we were on the same page. I don't blame him, and neither he blames me, it's just sad.
We decided not to stay friends and to fully move on. It's hard not talking to him. I had to remove him from all social media as well because it was eating me alive. I think every day about him, I catch myself fantasizing about his kisses, his touches, sex... about how he's doing and yes I also wonder if I made the right decision. I feel a bit of regret even though I know I did the right thing.
Why is it so hard getting over an ex, even when you know they are no good for you?
Add Opinion