Is it still normal missing my ex?

Its been five months since we broke up and I never understood why she did. I really did love her a lot and she loved me too, I think.

When we did break up it caught me by surprise. We were calling eachother on Instagram and she asked me a random question, "What would you do if we broke up?" I took that as a sign that she was joking since she did teased me on a lot of stuff like that. So I told her that I would be sad for a long while and immediately after, she asked to break up with me. I took that as a joke again until she said she meant it. So I started asking her why and she just said that I was too good for her and that she was a bad girlfriend. Mind you, she was a alternative emo person listening to ptv most of the time and was known for having a nasty attitude. I understood that she had a bad attitude but that never stopped me from loving her, so was just dumbfounded for most of the time. 

After a week or so after our break up, we cut contact and that led to me cutting most of people I knew off to make me forget about her and move on. I thought it would be a good couple of months of missing her before I moved on but I still can't get her out of my head. Its gotten to a point where it sometimes affect my other friends, but I rarely let them know how I really feel about it. I still sometimes see her from time to time but I never really had the courage to go up to her because I think she hates me. I just hope that I can lighten up about her and have a normal relationship again.

How do, or should, move on?