Should I just move on?

I'm in high school. I'm 17. When I was 15 I was in a relationship a girl at my school in my year. We broke up last year.

That time we were together is the happiest I've ever felt. We did everything together: We went to movies, baked cakes, babysat her little sisters, went to parties, and we almost had sex. We shared everything together and spent almost all of our time together. Then she got a job.

Now that's all over and done, and I feel really awful. Towards the end of our relationship she admitted to having feelings for a guy at her work. The thing I hate is that before she told me she was getting angry at me and almost broke up with me one day, but changed her mind at the last second. Eventually I broke up with her because we weren't happy with each other.

Despite being broken up we still spoke a lot, mostly about getting back together. I was miserable, she was miserable, and we felt even worse. So after a few months I asked her if we could, but she kept giving me reasons as to why she doesn't want to, such as work and family problems. There were times where I would ask if she wanted to hang out for the day and at the last second she would keep saying she had work. I thought fair enough. Then I asked if she wanted to hang out on my birthday (we spent her birthday together, and my baby brother was born on the same day so I made less time for that than I did for her), and she agreed, telling me she wouldn't have work. Then for a few days she decided to ignore me, where I know she was at a party that I wasn't invited to (it was all girls aside from a few boyfriends) and didn't speak to me on the day before my birthday. She told me she needed time to think about whether or not she wanted to be with me, and said she didn't want to see me for my birthday. I got angry at her.

Then I thought despite everything I'd be sweet and get her a Christmas present (a week after my birthday) and I got her a video game I promised I'd get her months prior (she thought it was cute, I introduced it to her). So I dropped it off at her work on Christmas Eve so she could pick it up later that day. I sent her several messages telling her to pick it up, and asked the following day if she liked it. I messaged her every day for a week, and she didn't respond once.

Finally I sent her a message saying "Go f*ck yourself" and she replied instantly, saying she was too "busy" to talk (when I know she had still left plenty of her friends messages the week she ignored me), and I asked if she got her present. She said she looked on Christmas Eve but couldn't find it, which I know was a lie because she hadn't spoken to me at all and couldn't have known I got her one. So I told her to go f*ck herself once more and we didn't speak until today.

Last week I got drunk once and I called her heaps of times in order to tell her that I still want to be with her but if she wants to be with that guy she likes (I know they were together on New Years Eve) then I'd let them, and she didn't answer once. Eventually it got to the point where her friend told me that I should just move on because she has, and I stopped trying and just completely put her out of my mind.

We're in the same class now, and she send me a message, jokingly calling me a "dikhed", and I asked her why she messaged me and what made her think we were on speaking terms. She said that she wanted to talk to me (didn't give me a reason why), and I got into an argument with her, where I told her that I wanted her, and she said she has moved on. So I told her "Fine, don't speak to me ever again."

So with all of that being said: Should I just move on? Is there absolutely anything else I can do?