You're still grieving from being hurt which is a completely normal part of moving on.
You think about him and care that he appears to be doing well. Time will slowly make him and any thoughts associated with him disappear. You need to worry about YOU not him, everyone pays for what they do at some point in time. "We must all face or demons eventually." that line is true in so many ways.
I was stuck in this phase for a long time after I broke up with my ex. She treated my like shit and walked all over me because thats the type of person she was. I felt cheated and betrayed even though I was the one who broke it off. I held onto that bitter sweet feeling for 4 long months, then she did something that kind of sealed up the kind of person she really was and I started moving on that day.
I work with my ex, but beyond that I have no idea where she is or what she does. She shows up to work now and then, so I know shes not dead and thats all that matters to me. I don't wish her harm or bad luck, I just simply don't care about her anymore than I care about what song I listen to on the radio.
There was a time when I thought I would never forget about her, but you eventually do forget about them. I erased her number and contact information long ago and to this day I couldn't tell you more than the area code of her phone number. I find it rather amusing, I couldn't remember her phone number if it was the million dollar question, but I know she still has mine because she comes around now and then to make some pathetic attempt to get me to talk to her.
Life's not about being fair or getting even, its about getting the most out of it that you can. Hit hard and hit fast, we all die eventually.
Edit: A good way to gauge your progression past a bf/gf is whether you can listen to songs you shared or they liked without having an emotional surge. Two songs we use to listen to are actually two of my favorites that I listen to regularly. "Chasing Cars - Snow Patrol" and "Only God Knows Why - Kid Rock (hard one to find)"
