I feel like an old curmudgeon posting this but honestly, a wedding is just a wedding. It sounds like you have a posse of girlfriends that you used to go out partying with and now, one by one, you are all getting married. This happened when I was in my early 20s. Quite frankly, as the bride, I would register that someone was there at the wedding but it wasn't a deal breaker if someone wasn't there. The whole evening passed by in a whirl. It was the other guests who would notice. If you get drunk and blackout. Dance on the tables. Start crying in the ladies room over some perceived slight. Slur your words. Fall down. Look glassy eyed and repeat yourself. Puking in the bathroom. Puking on yourself. Your hair starts falling down and your makeup smears into sweaty globs. I'd say skip the reception or if you absolutely want to go, leave after dinner. Even that is fraught with danger. Wine with dinner. The champagne toast to the happy couple. "Oh, come on! Have a drink. One won't kill you!" Or the twenties "what? Are you pregnant?" I used to think that was the worst thing in the world to be asked. It isn't actually.
It's great that you're thinking of this now. Hang in there. We've all been there at one point.