Been there, done that I was 39 before I married.

I was thinking, were I you, I'd go to the wedding with your parents (not mess with the guy friend whose girlfriend may not like it?) with the purpose of checking out the other half of the bridal party, seeing if you can meet any guys (or girls), decide you want to make "3" new friends and use the event as an experiment. Most people will be from far away and not anyone you know well besides your parents and siblings. I know I did okay with older folks too, as well as children, maybe you can meet a neat great grandmother and hear her stories or meet someone who works at an occupation of interest to you or whose stories give you an idea for something you'd like to try (once you get home :-) Use the opportunity to try new things without as much risk as there would be otherwise. Maybe study the town/region you're going to before the wedding and see if you can go visit some site of interest to you and drag a few others along with you; maybe there's a amusement park of some sort or wave park and you can write some of your family/cousins and tell people to bring their swimming suits for a joint outing the next day, after the wedding.

I had the same younger-cousin get engaged thing and her fiance gave her a rock of a engagement ring whereas my husband and I weren't into any engagement ring at all particularly. But, I dragged him out and we bought a cheap ring just so I'd have one! I know what that assumed family pressure can do! But, if you think of your own agenda, you don't notice/think about what the other people are thinking/doing as much. Don't try to "conform" when it's difficult, since you are "different", be different and have a different agenda, all your own of what you'd like to do with a party/new people to meet/places to see and things to do (and great meals to eat? :-)

P.S. There was no orchestra/dancing at my wedding because I don't dance either :-)