I went to my best friend's wedding last September and spent a little less than what this survey reports. I was also the best man so I had to drop a LOT more cash than the other groomsmen.
(My best friend on the left, me with garter on the right)
According to YouGov, the average person spent close to $1200 just to ATTEND weddings. This includes traveling, hotel stays, and wedding gifts. This amount is COMBINED for every wedding attended during the year as well.
If you are asked to be IN the wedding then it's costing you a lot more. The bridesmaids will spend an estimated $1,149 per wedding where as the groomsmen will spend $980 per wedding.
I think I have three weddings to go to/be in this year too. My wallet is going to hurt so bad :(