I went to my 10th HS reunion and went with my husband to his. (We went to the same HS and his was 2 years before mine.) When I walked into mine, the first thing I heard was a girl saying to my husband, "You are still with the blonde?" (Yep - and he still is.) And a little later I was in the rest room and while I was in the stall, one girl that was married to an old boyfriend of mine, was talking about how stressful it was since I came. (Not sure if she knew I was in the restroom or not.) OMG, I was not that popular in HS and I suddenly felt I was back in it with all the drama. I was the school newspaper editor so knew a lot of the students and didn't really hang out with just one group. I thought I got along with almost everyone. Didn't think anyone would be upset that I would be there. The one girl I was hoping to connect with was not there, she did attend the 20th but she didn't give my SIL her address, so that was that.
It's now 42 years since HS and the ones that I wanted to keep in contact with I did and the rest, oh well. My HS best friend died last year so really have no reason to return.
My husband has gone to a few of his reunions without me (he took our youngest daughter), he enjoyed them until there was no one willing to plan them anymore and we are too far away to try. They merged two HS's together so any reunions now include both schools - which is funny since they were rivals back in the day.
Maybe if they had been held at the school instead of in a ballroom at some fancy hotel it would have been better. Not sure - just easier to look forward than behind for me.