[caddemon]

It really depends on the situation IMO. "Sucking it up quietly" doesn't necessarily mean that the entire event will be unpleasant. Sometimes it is more like the activation energy necessary to stick to an exercise routine - if I had a draining work week I'll have low motivation to go out, but if I do "suck it up" I'm usually happy at the end of the night that I did.

The social pressure to "suck it up" can actually be an awesome motivator for healthy behaviors, e.g. committing to a rec sports team. So there is definitely variation here. You need to know not just how important the event is to your friend, but also yourself.

[em-bee]

right, it depends, if the thing that agreed to has some other benefits.

an alternative example would be after that draining work week cancelling an activity because i know i'll be tired the next morning and i really need more rest to be fit the next day.