Dear Prudence,
My family recently learned that my wonderful father-in-law has a very aggressive, incurable form of brain cancer. He had surgery to remove the bulk of the tumor and has lost the ability to perform many basic skills like driving and reading. He is currently undergoing radiation and chemo, which the doctors say may give him anywhere from six months to two years to live. My father-in-law is 88 years old and has been very healthy and active up to this point. He says he has lived a good life and wants to have as much fun as possible in the time he has left. My in-laws live just a few blocks from us, so we have become very involved in their daily lives. My husband is very close with his father and is devastated by this turn of events. He immediately began researching various cancer treatments and has tried to convince his parents to adopt an ultra-healthy diet. My in-laws enjoy a nightly martini and eat white bread and prepared foods. Despite bombarding them with supporting evidence, studies, videos, books, and every other persuasive technique possible, they are adamant that the whole thing just sounds like hocus-pocus. My husband takes his mother shopping and scrutinizes every single item she buys. When we eat together, he says things like, “Mom, if you want to eat that, it’s fine, but Dad shouldn’t because it will kill him.” I tried to explain to my husband that his parents are adults and we cannot make them do anything, and he responded that he would never forgive himself if he does not “take this issue to the mat.” What should I do?