If you are talking about other people's birthdays, I have an idea. Decline the invitation using whatever excuse you have to, then invite them to dinner one on one.
Make it at your place if you can or find a couple of really cool non-bar restaurants and take each friend out one at a time.
Nobody remembers those bashes anyway. If you have a friend to a special one on one dinner--after (AFTER) the big party, that will be more special. You aren't upstaging the party, just making sure you acknowledge the event.
Good luck.