The act of sending a tweet in which the user reflects on a sentimental moment of their life, i.e. a graduation, the end of a life period, or the passing of a loved one.
"OMG No longer in high school!!! Gonna miss it but moving on to bigger and better things!"
"RIP Grampa Joe. You lived a great long life but I'm glad you're in a better place now."
"All these bittertweets are bumming me out, man."