Just Fucking Don't Know - shorthand for a decision with no clear, right answer
Ex 1. The store left one of those anti-shoplifting magnets on my shirt. I think I'm going to have to cut it or tear it out eventually. JFDK...
Jim: Hey man, you going to the party 2nite?
Steve: Dude, I'm in so much trouble, I jfdk.
A slang term used on the internet to mean "just fucking don't know"
hey man, you going to the party 2nite?
dude, im in so much trouble, i jfdk