Is it normal to only have feelings for the same girl for 4 years?

In my early teens, I never really had a "Crush" or "Liked" any girls, until one day...

A girl transferred to my school, where we later bonded. We had a jolly time, texting the afternoon away and spending approximately 40 minutes with each other a day (What do you expect a dumb, young teen to do?). All was well until a variable interfered with our relationship (Not specifying for personal reasons) and I reacted poorly. I got depressed, I said terrible things to her, and I tried to push her away (Figuratively). Overall, I acted like a psychopath. We didn't communicate much after the incident.

It took me months to recover from my depression and selfish thoughts, but I eventually got my act together and apologized to her for my behavior. She forgave me with little to no hard feelings. We still don't interact much (In fact, we exchange less than 6 words a year). I like to think back to relationship and wonder how I could have handled the situation better, but there's nothing I can do now.

With the apology, the remorse left, but not my feelings for her. I never had a crush on anyone before her or anyone else after her. I could tell by her new boyfriend(s) that she has moved on, but it seems as if I can't. Most people move on after a month or two, but here I am, three years later, still thinking about how I let the most beautiful girl I have ever seen escape me.

I'm not trying to get her back. I am questioning if I have some issues.

So, is it normal to only have feeling for the same girl for 4 years?