When someone breaks up with their partner, and quickly rebounds, subsequently dumping, or being dumped by, the rebound. The person becomes doubly depressed as they didn't properly grieve for the first relationship, so are projecting their feelings onto the rebound break up.
"God, She really needs to get over Stan. They only dated for like three weeks and she's so cut up about it"

"Don't you know, she broke up with her boyfriend of 2 years just before. It's just rebound double depression"
by Doublydepressed September 17, 2009
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