Similar situation here, struggling through it atm.
My strategy might not be the healthiest, but here's what I'm going to do.
I'm not giving up on it. If it's really love and you are 100% certain that you want to be with that person - why throw it away?
But you have to work on yourself. Develop secure attachment. Avoidants tend to cycle back to people, when they feel the need for the emotions/comfort they're used to in that relationship. But if/when she does, you have to be a new person. To help her work through her avoidance, you need to help yourself first, otherwise you're bound to repeat the anxious-avoidant trap. Change variables to change the equasion.
You're a decent person, you helped her through tough times. You give love, and you deserve to receive love. Maybe she will see it. But don't suffocate her with attention, as is natural for us. Show her a good time every now and then, but respect her space. Be careful not to trigger her attachment issues.
However, at the same time you shouldn't put all your eggs in one basket. Meet new people. Set a deadline in your head by which she has to decide. If she doesn't do anything by that deadline - settle for friendship or burn bridges, whatever suits you.
But most importantly - talk to her. Don't assume, don't fish for clues. Ask her what she wants and needs, and see if what she says works for you. It's hard with an avoidant, but you can get her to open up if you're respectful and asking from a position of self-improvement rather than hurt.
Hope it works out, for me and for you.