Can’t speak to others’ motivations, but my wife had to “keep the peace” with her grandparents by seeing them on Christmas, even though they were awful people who took pleasure in bullying and belittling her mum. If we didn’t show up on Christmas for an hour or two and put up with some snide comments and a few “I’m only joking don’t be so serious”, then her mum would have to put up with months of full on abuse.

We didn’t need substances to cope with it, but I can totally see how people might feel like a drink or a toke with some family they do enjoy socialising with could make it easier to be with family they don’t enjoy spending time with, but feel obligated to to avoid hurt feelings.

For whatever reason my mother in law didn’t just cut contact and leave them to die alone in their crappy little house surrounded by their hate and resentment and friends who also couldn’t stand them. Thankfully they are dead now, so we don’t have to put up with them.