There are people that I wouldn't mind going to their event if it doesn't overlap something else. But I might be going by myself, as VorGuy has things set up that he can't miss.
During the school year, VorGuy's weekends tend to be tied up 3 out of 4 weekends (football games, drill meets, community service events, practice for drill meets, even a couple of field trips that go overnight once or twice a year, and similar events). So if there is something else going on that weekend - it is probably not going to get an RSVP until he tells me whether or not that day is already scheduled or if he is going to have enough energy to go (at 50-something, we have less energy to spare than we did ten or fifteen years ago - we RSVPed "maybe" to a wedding that he got home at 6 pm the night before and ended up sleeping late, so we missed leaving on time to get to the wedding).
Ironically - the wedding was in the town that he'd left at noon the day before - but he was driving a van full of students home, so couldn't stick around for 24 to 28 hours until after the wedding....and nobody else was able to drive the rental vehicle....the lease was for him and only him to drive.
Summers, he has summer camps (in and out of town), practice sessions for marching, and some training set up for students who have requested it - July is the only month without school obligations - and we own time shares for vacation that we book for two weeks or so for OUR vacation. He does NOT give up his vacation - although he sometimes will book a few days for just himself - he's an introvert and finds going to group events with me to be less relaxing than going jogging by himself.
There are times when you can't go to everything that you'd like to go to - time, distance, cost, energy levels, and other obligations have to be considered and weighed. If people don't understand that - well, that's too bad. Making yourself sick from lack of rest to go to parties isn't a good idea, whether you are seventy, fifty, or thirty . Although most people have more energy at twenty-five than than they will at fifty (or even at forty).