it kills me that she doesn’t feel it back…

I’ve liked this girl, M, for around 2 and a half years now, though I have never been able to tell her. I am a 17 year old male and she is the same age. We used to be quite good friends for the first year I liked her, we caught the same bus to school and would talk quite a lot during bus trips. We started to become quite open with each other, if we had problems we were able to go to each other and talk to each other about it. I loved having her there for me when I needed it, she was always so caring. I had always wanted to tell her how I truly felt about her, but I never thought she liked me in that way back. I was scared that things may become awkward between us if I told her, and I valued our friendship so much that I did not want to lose it. During the first year of liking her I started becoming attracted to another girl I didn’t even know, I started spending lunchtimes with her and she figured out that I liked her. We never started going out, as this girl told me she did not like me, I was never to fussed over her anyway. During this time M started going out with a boy, it did not last long however. I don’t think she has gone out with anyone since, from around 2 years ago. I still liked M a lot, and this feeling grew. We were still good friends. One day after school I came and sat down on the bus beside her as I usually would. She held onto my arm and asked me questions like how I was doing. I had just had PE and was quite sweaty, I told her she didn’t have to hold my arm because it was all sweaty. But she did anyway. I don’t know if anyone else would interpret this action in the way I did. I interpreted that she held on to me even though it may have been slightly unpleasant holding on to my sweaty arm, she was there for me even if it didn’t suit her. Maybe that’s stupid, I don’t know. But I do know that my feelings towards her grew significantly by this action. After a while she stopped catching the bus and would drive herself to school. I hated that she was gone, I missed our conversations so much. We barely ever saw each other as we only had one class together and we have different friend groups. Our friendship started to die away over last year, to the point where greeting each other if we walked passed one another was unlikely. I suppose I could have made more effort to talk to her. I reminded her a few times that I was always there for her if she needed anything or someone to listen to her. At times I questioned myself whether I should like her, at times I even tried to discard my feelings for her. I was unsuccessful, liking her felt so right, she felt like the perfect person to be with. This year I decided to ask her out for coffee, I asked her casually – so she didn’t think it was a date. She agreed to and sounded quite keen on it. The school ball was coming up and I had always wanted to go with her to it, always I wanted it to be her I went with. I asked her, I was so nervous that my mouth dried out. I had expected her to say yes, but she replied saying she had already asked another person. I felt like I had been ripped in two, I could not believe it. I had always dreamed of going with her. Going out to coffee with her was great, we got on well and caught up on a lot of things as we hadn’t had a decent conversation in a long time. She lived just over the hill and had walked there so I walked her back home. The next day I called her and asked if she wanted to catch up again soon, she replied saying she would rather go in a group. I didn’t really think she sounded overly keen on doing it. I made more effort on going up and talking to her at school, a few times we would have alright conversations. Then one time I tried going up to her and making conversation but she kind of just walked off as she was answering. It hurt that she didn’t really want to talk to me, it hurt a lot. For the next 2 weeks I was deciding whether I should tell her I like her or not. I knew she would say that we should just stay friends, but I really wanted her to know. She needed to know how amazing I thought she was. Finally I pulled up the courage to tell her. She looked really happy when I told her, I told her I thought she was amazing and I cared about her a lot. But she said what I knew she would say, that we should stay friends. She also said she wasn’t ready for a relationship. At first I wasn’t all that depressed about it, I was glad I had actually told her. But here I am on the day after when I told her and it has really sunken in. I’ve liked this girl for so long and I do not want to stay friends, as friends in our situation we barely see each other. Today at school was so hard, when I saw her I knew that she knows how I feel about her, but nothing was different. She means the absolute world to me and I would do anything to make her smile in a split second. I love her. Every time I see her face everything feels perfect and I feel happy. I love her so much and it kills me that she doesn’t feel that back. I understand she isn’t ready and I would never try pressure her to be.
I wish I knew whether she would want to become more than friends in the future.