so confused

I dont know what im going to do without her. She was my bestfriend at least i thought. I wasted 3 years of my life in some friendship. You might say friendships come and go.. but ill tell you why this one was diffrent. We were more then friends at one point. She started it and i went along with it just so happy that someone loved me. One night when she stayed the night she put her arm around me and that was it. Its as much as my fault as it is hers i didnt stop anything. Nothing serious ever happened just cuddling and hugging. One day she was over she kissed me on the cheek. I didnt know what to do so i just looked at her and smiled and then sprawled out more on the couch. I never wanted to be intimate with her. I think it was just having someone to hug all the time. This went on for a year and slowly fadded. Till she would push me away and i didnt know why. Dropped like nothing I was. I thought she hated me or I did somthing wrong. I didnt understand what I did. I finally confronted her she said she wished it never happend and she was sorry…The thing is she said it like it was nothing but i actually had feelings I loved her she was my bestfriend. I understood though it was hard but i got over it. I relized I was never sexually attracted to her. I still wanted to be her friend and she said she wanted to be my friend i was like her sister she told me. Then she slowly stopped talking to me.( we have another friend that hangs out with us) and she just started being her bestfriend and completely ignoring me and started treating me like crap. I would say one word and she just snaps at me and puts me down. There was a point in our friendship were i was her bestfriend who she would tell anything to. I never wanted to lose her as my friend cause I knew some where in her was her old self that would talk to me and want to hangout all the time. but I guess I was wrong. Today I told her I had enough. She agreed to everything i said and how she treated me when i was around her. She said she didnt know why but little things i did bugged her to the point of wanting to scream…..( i barley say more then 2 words to her a day and i never seee her) ofcorse i didnt know what i didnt and she could tell me what i did eaither. She wouldnt tell me yes or no on wether or not she wanted to be my friend but she made it clear. I told her im tired of wasting my time with a person who dosnt want to be around me and im tired of putting in so much effort and being treated like crap right back then she said then dont. Thats all I needed to hear. I told “ok then I will…call me if you change your mind”. I know this all sounds stupid even i think it does when i go back in read it, but for some reason the pain is just so unbarable and i dont know why? I prepared myself so much for this and i have other friends so i have no reason why im in so much pain or how to make it go away? Im so affraid of death i even cry sometimes just thinking about getting older yet it seeems so easy. If things keep going down hill I dont know what will happen to me. Im already an emotional person and things like this just dont help. im open for advice