My family live abroad, couple of hours on a plane. I've visited 4 times in the last year (I hate going due to a combo of bad memories there and not enjoying being around my sister since she became a mum) but try to make an effort.
I've booked with partner to go out for nephew's birthday, it's a small at home get together.
Due to partners work/cost of flights we arrive on the day of the party a few hours after it starts but are staying 3 subsequent days. I've just told my sister and she's got in a massive huff about us missing the party and why couldn't I have made the effort to go the previous day.
I'm now tempted to just not go altogether, we have not gotten on at all since her having a baby. I feel often like she talks to me like a bit of shit on her shoe and I'm essentially a glorified slave when I visit.
Any attempt from me to help with anything is met with 'Don't do that, you can only help if you do exactly what I say, why did you do it like that?' Etc.
It's not in my nature to be confrontational but I'm getting so fucking pissed off.
So...
YABU - suck it up and go to the party
YANBU - I wouldn't go either