Having seen elderly people decline, I honestly wouldn’t be surprised if it’s simply that that have a help network in place when they need it. I actually have a widowed neighbor approaching 90 with limited mobility but she’s been able to stay in her home comfortably enough because we have a rotation on our block that brings her meals (eg. We feed her on Wednesday, etc). She doesn’t really need the economic support but having someone cook and prepare and clean for her at each meal is a reason many people her age would move into an assisted living facility. Despite a high degree of social contact, duration of life once entering a facility like that is pretty low. She’s across the street from me so I even go take out her trash weekly to the curb and make sure her lawn guys are keeping things up to her standards (simple stuff like “hey, can you fix that sprinkler head”)

Alcohol consumption could be something as simple as being a net positive for health in moderation after accounting for the impact of various stresses the average person encounters in life. These things are often encountered as a couple for married folks.