I know this is a very difficult time for you. Your powerful and moving description of this relationship highlights how difficult it can be when our love isn’t returned. Unrequited love leaves a vacancy that can be hard to understand, hard to fill, and emotionally burdensome.
But it also provides perspective and reevaluation of our emotional needs. When a good relationship has ended, one way to reframe the feelings around it is to recognize you were in love with that person’s potential. Not her reality. It was good up to a point — but it was limited and those limitations were real enough to cause it to end. The good features may have eclipsed the not-so-good ones in your memory and can dominate your thinking about the relationship. Use what was good as an indicator of what is possible. Seen through this lens, you can understand the relationship as a signpost of what you want more of in your life, not as something you have missed out on.
That having been said, and seeing as how you have tried so many ways to move through and past it, I would recommend learning something new — a new skill, a new language, a new sport. The shift now should be back to your own development and learning something new can help you absorb the transition out of this relationship.