I'm an old fart now at 32, but I was 23 when I got it. On my 23rd birthday to be precise, at least my initial injury was. Your friends won't understand but hopefully they'll be willing to learn. Some of mine did and some even sent me links to new research but for the most part they didn't. You'll find that even a lot of Doctors are not educated about it so it's hard for our friends to be. I like to show people the McGill pain index now with RSD on the top. (look it up on google because I think links get broken). If a friend thinks you're being a party pooper, show them that chart, perhaps it will teach them to be a little more sympathetic. I also initiated a lot of things I was able to do so that my friends didn't always feel like I was ditching them. I just couldn't do a lot. When I could, I would make sure to invite them so that we didn't lose touch. Good luck to you! You're going to get through this.