Is it normal to feel upset and want to cut ties?

I am unsure why I am feeling like this. I have had this friend since middle school and I do enjoy being around her but she acts like she is too much "It's all about me" and has her occasional "mature" moments. She has helped me through a lot of things in my life and I do appreciate her but lately I just feel distant from her. The things that upset me lately are memories that keep coming back.
Throughout high school she acted like a princess and pushed me away in high school and then got reconnected back in college but I cared about her a lot so I didn't care. There were plenty of times I was going to leave her but I didn't. I had more patients back then but now I don't. but I realized that the only reason I stayed with her was because I was a push over and I hate that. I have a hard time letting go that she controlled it seemed two of the guys who were my friends for a while and she avoided me then. They even said she acted like a princess and avoided her for a while. I thought I forgave and forgot but now bad memories are coming up. Not to mention She likes this one guy whom really got on my nerves and we aren't friends anymore but she continuously goes after him. It's not healthy. It felt like she just used me when she had trouble with that one guy. After a while I got fed up and started to get upset so I blocked her on facebook messenger. When ever something happens that causes her to have a fight with him she spends time with me. She forgot my birthday as well as other good memories we had together and I feel like I'm ready to move on. Recently I blocked her on facebook messenger and she found out. I posted recently about something cool that happened and then she comments that she's not receiving messages. She isn't replying to me and I lied and said "It's just a error probably." I've lied before and feel bad afterwards but this time I don't feel bad. I don't think I'm important to her and I don't think she values me anymore as much as I value her. She will probably think I'm a liar but I don't know how I feel about it. I really wish I would have cut ties in high school. I'm not special to her anymore.
How do I move on? Is it normal to feel like this? I feel petty because of blocking her messages. I'm usually really forgiving but I feel like I'm to my last straw. I don't want to hurt her but I've known her for a while and now I am just not sure if I want this person in my life. I know she lives far away now but even when she returns back home where I live close to she never got in contact with me. She's become friends with people I would rather not be around and I am trying to be mature. But I feel like I don't want to deal with this right now. I want to cut the friendship but yet I never know if she'll grow up. I don't have many friends because I am very selective of them. I am more productive and choosy with people whom I want to hang out with now since I am older. I don't know how I feel about her anymore. I don't feel like she really cares.
Is it me or is it just my imagination?