Most Helpful Girl
It's obvious you both care deeply about each other. If your problems are ones that can be solved, for ex. Someone is always late, or mood swings, that can be worked out. If you have bigger issues, such as trust, or one of you doesn't want the same future, then it might be best to let it go. I do know that relationships like that when you feel so strong and deeply connected to someone, don't come around very often in life. Good luck!
Most Helpful Guy
If she is done and adamant about moving on, then there is little you can do to win her back. However, I'm assuming she is conflicted about the relationship, the breakup, and what the future potentially holds, as you are. For this, I suggest you give her a few days of space and contact her after to make your pitch to be with her, without pressuring her of course. Expect some resistance of course, and be patient.