Is there any hope that she will see heart surgery as a wakeup call?

My spouse's mother, a senior citizen, just learned this year that she has heart failure. She survived multiple heart surgeries recently, a harrowing process during which she said she never wants to go through that again. Great! We assumed this meant that she was seeing this as a wakeup call to change her eating/exercise habits and stress levels so that she could get healthier. Several weeks later, it turns out that she is going back to all the old habits that helped contribute to heart disease in the first place. Is there any hope for her changing her deeply-ingrained habits? If so, what can my spouse do from afar to help support mom? If there isn't any hope for her adjusting her lifestyle, then how can we learn to accept her choices and still give her the support she needs? We live far away from her, and my spouse has spent much time visiting, patiently trying to help her choose healthier foods, and cooking at home. MIL who lives alone, won't cook for herself, and has also rejected the idea of hiring a personal chef, or eating prepackaged meals. She prefers to continue eating at the same restaurants, and will order foods that are not considered heart-healthy at all, or very unbalanced in favor of sugar/salt. While she is certainly stubborn, she is also quite possibly confused because she has received many conflicting opinions on how to eat healthier, both from her doctors, and from society in general. The good news is that she was never a smoker, and only drinks rarely.

Specifically, I'm looking for A) examples of people who had major "wakeup calls" and drastically changed their habits at an advanced age. What is required from an emotional perspective to be able to reverse such deeply ingrained habits? And B) How can we better accept a person's choice to refuse to change their unhealthy habits?