Is it normal that i miss my ex even though i don't want him back?

So, my ex was my first boyfriend, the first guy I had real feelings for. I was crazy about him, loved him so much... Actually I was kind of obsessive. Which I think is because he was so on and off with me. Most of the time he would tell me he loved me, but then randomly he would disappear for 24 hours (it was a long distance relationship for the majority of the time, so if he didn't text me I didn't know what was going on). He would take forever to reply, he'd randomly hurt my feelings, i just felt like he didn't act like he loved me that much. Anyway, so we broke up. Afterwards, I got into another relationship almost immediately, this guy was super nice and I was very comfortable. I stayed with him for 2 years, and ignored any approaches from my ex who told me he missed me about 3 times during that timespan. A few months ago I noticed he had been in a relationship for a little while, so I asked him if we could be friends. I missed him everyday for the past 2 years, even though I was trying to be strong, and it helped me to somehow be in contact with him. However, he started telling me he missed me, so I had to stop talking to him. Apparently he broke up with his girlfriend and stayed single for two months after that. And about a week ago i noticed he was back together with her, so i asked him to change his facebook profile pic, which was a picture i had taken of him on one of our dates (he had changed it when he broke up with his girlfriend, and I had ignored it bc I didn't want to get involved, and I was hoping they'd get back together). I didnt want it to be a problem now either because I wanted them to still get back together. Then 2 days ago I broke up with the guy I was with because I realized he made me feel comfortable, but I wasn't excited about our future at all, and I missed my ex every day. Anyway, now my ex is back with his girlfriend, and after I had asked him to change his profile pic, we kinda kept talking, each asking how the other was. I didn't tell him I broke up with my boyfriend, but I just kind of got him to confirm that he wanted his new girlfriend over me. (He told me he had to move on bc I chose someone else over him). And.... It hurt so bad! I don't understand. This is what I wanted. I wanted him to get back together with her, logically it makes sense. We had an on and off relationship for a while near the end of our relationship where he would tell me he would change, but he never did. So I know, it would just be the same and we would break up again if we tried again, and I really don't want to jeopardize his new relationship. Seeing them together makes me feel like im burning from the inside out. Gaah, I just miss him so badly all the time, even though I was sad so often while being with him. Anyway, sorry for the essay, but... IIN?