I wish I could ask my father that question. He stayed with my mother, and managed her alcoholism, for forty years, and when his eventually health failed him she was not capable of returning that care and attention, or to even express gratitude for all he had done for her. I wish I could ask him if it was worth it, if he got what he wanted, that if he'd known what he was in for if he would have left earlier.
For my father, "hope" was his only plan, "denial" his only support. It seems he was unable to look past the person he wanted my mother to be in order to see and accept the person she really was.