You don't have to go if you don't want to. But if you do, ask your friends to accommodate. That's what my friends have been doing. Any decent and understanding person would.
I went to a graduation party this past weekend. It was really a brunch. It was so loud even my 8 year old asked to go and said it was too loud. I wore earplugs, but it was still too loud. I think next time I'll stay a shorter amount of time.