Alright, so there's a girl I met at uni who's now getting married. We're not close at all, but she's been very kind and invited me to her wedding. Evening only.
As the wedding is hours away, there's only one hotel close by with ridiculous rates, and I'd only be invited from 8:30pm anyway, I'm planning on not going. I went to go and click the 'sorry, can't make it' option on her RSPV website when I saw the ride share list on there.
I've been put down to drive (what appears to be) one of her elderly relatives from my hometown. Never offered this, have never met the elderly relative in question, haven't really spoken to the bride about the wedding at all 
Messaged another friend who's been invited to evening early and is down on the list to rideshare with someone elderly, same thing with her!
I've never declined an invitation so fast. Not sure if I've been invited as a friend or because I've got a car and happen to be from the same place as her relative!