Rethink your play style. I sucked at Crucible for a while. But recently started getting better. I've dominated with all three classes, seen many times where a Titan wrecks the other team. Just think on the situations that you got owned, and learn from them. Figure out ways to turn the tables. But don't sweat matches that don't go well. There are always people out there that are just too good, and will wreck your shit no matter what. Lastly, it's just a game. Have fun.