A practice, often enacted by single people together on Valentine's Day, of masturbating while commiserating over the lack of romantic or sexual prospects.
To mark an occasion that is worthy of celebrating yet also feels like you are due commiserations. Birthdays that make you far older than you want to be, or to mark the end of a relationshit sad that it's over, but glad that you're single.
I commiserate for several iterations of back and forth, then someone actually identifies what they are stuck on and I can often quickly offer a suggestion/fix.