When someone can't make up their minds about something or can't quit something.
Tom: I'm not sure if I want a cheeseburger or hot dog.
Dan: common dude you're Favrein' It!
Jacob: Damn, I went 3 months without weed but yesterday I just had to smoke some and i can't decide if i want to quit it or not anymore.
Alex: Bro, your're Favrein' it, make up your mind.