All i can say is, if you are losing that poorly and not learning anything from your losses, than you DO need to walk away from the game. Losing in GG/BB usually shows me something, but if its to the point where you a losing before you play the match, than you should probably take a few hour break from playing. stepback and reconsider the way you are playing the matchup/person who you are trying to beat, and come at it with a fresh set of eyes, and the willingness to take something from a loss.
Whoever said drinking alcohol doesn't help, you are wrong. The 2 times i played online drunk my win% went way up. A complete lack of care for the opponent is why.
To shorten it up:Think youll win, get drunk.