Is it normal for infatuation to end after all these years?

For about a good 4 years I was very crazy about someone. I basically thought about them all day long and no matter what I did I just couldn't get her out of my Head.
I was never able to tell her how I felt because we were close friends and the fact that I'm a girl and we are straight I just was afraid how she'd take it. I know I could have possibly told her as she was an open person but I was still terrified. This had never happened to me before and idk how it started. I loved her but she did a lot of things in our friendship that hurt me. I have just realized over the past 1/2 year that I'm not obsessed with her anymore and iv actually finally moved on! What causes one to suddenly stop being infatuated ?