I agree with ST and Ovr, you're letting her cake-eat and now you are stuck in the friendzone. You are Plan B. She's not coming back as long as that keeps up. I understand it's difficult not to let her continue the cake-eating because it's a way for you to have some time with her, but is it really fulfilling for you or does it just keep hurting you worse? I think your best path forward would be to tell her you can't continue the friendship, so if she's not willing to commit to work on the M then you are done with her and you need time and space to heal and recover. Paradoxically the time away from you might make her start missing you and realize what she's losing.
