Rebuy Turnaments
I have found that on occasions I lose with a pair of Aces, Kings, queens and otherwise had a fantastic game going. All-Ins are worrisome but can be overcome. Simply don't fall for it. Hard to do sometimes.
Otherwise, I have found if I play my game and don't fall for All-Ins, I do OK. I know how you feel, though. When I am in the top 25% and see that there is another hour of rebuy time, it can be very discouraging.
Good luck.