Not to be insensitive but the old joke comes into play there.
Why do married men die before their wives????
Because they want to.
But what you said is correct. The will to live is the most powerful cure there is sometimes.
Sadly, the “joke” is dead on accurate in this situation. He married his high school sweetheart a little less than 50 years ago. (Time goes by so fast!) She was a beautiful young woman but their were plenty of warning signs before they got married that problems were just around the corner. She started puting on weight immediately after they got married and has been a morbidly obese nasty witch ever since. He completely lost control over his life. Even the obituary posted on the internet was all about her.
He made the one attempt that we know of to escape... we both feel very bad now that we did not support him. It ran against what we believe about marriage, divorce, and family. But we knew he was miserable and had a miserable life. It was a waste.