I kindof identify with what you said here, in that it doesn't matter to me to be at those things for someone who isn't very close (siblings, parents, close friends - in theory, since none have happened yet, thankfully!). I do feel the social pressure to be there, though. There would be more pressure if you're close to other people who are affected by the death and who want or expect support from you.
I also haven't visited my grandfather in long-term care in the hospital (about a 10h drive away) for several years, which I feel guilty about when I'm reminded, but not enough to visit. My first (and last) visit was pretty hideously awkward.