Get the old version of you out of your head. All those promises and hopes, are they holding you hostage or increasing the quality of your life?
Were the sacrifices of old a gift? If yes, you're allowed to say no. You can decide to put them aside, sunken cost fallacy and all, and move towards a new future.
How many times can you start again? Dream a new you? As many times as you wish. If you believe this is true, find that contract between who was and who will and tear it down the middle.
Allow yourself the grace to begin again after many failed attempts.