Trying to manage breakup, still hopeful and not able to move on?

My girlfriend broke up with me 3 months ago after a relationship that lasted over a year. There was a bit of strain on the relationship after I started college and she was still finishing high school. However, I still lived at home and we still saw each other on a fairly regular basis. We went through a period of some pretty heated arguments and towards the end, we had been improving on it. Her decision to end our relationship came at a very bad time. 2 weeks prior, I had a suicide in my family and it was very hard to cope. She was well aware of the situation and I told her that I really needed her for support. However, this didn’t seem to phase her, and it feels as if she literally just decided to kick me while I was down. It was just so hard to fathom that after all the time we spent together, she would turn around and hurt me so badly. It sent me spiraling deep into depression: uncontrollable shaking, unable to hold food down, nonstop crying. It had a bad impact on my grades and caused me to lose lots of weight. The way she left it was that she wanted to be “friends” and that she just needed “space” for now. As much as I may want to be friends right now, I know that I can’t be in contact with her so I can protect myself during this vulnerable state I’m in. The thing that now hangs over my head is the upcoming prom. I was supposed to go with her, and already paid my money for the prom weekend house. She kicked me out of the house and I’m not confident I will see my money again and she claimed that she is going alone, which makes no sense. So now this is coming up next week and I am really dreading it. The way she’s composed herself throughout this process makes me think of the way you would kick someone to the curb after finding out they cheated. I never did that and I always tried to do as much for her as I could. It just feels that shes been so harsh to me and it really hurts to think that I thought she cared about me. The most painful part of this whole thing is that I miss her, I still want her, and I still love her. These feelings haven’t changed at all and they just consume me every single day. The physical pain is often there too. I still feel as though she never gave me any closure because I still have so many unanswered questions. It’s just so disheartening that the one thing that brought me so much happiness and joy has now left me just a miserable shell of my former self. There is nothing I want more than to have her back. Any words of advice would be greatly appreciated. Thank you.