Problem is the random people you run with, after one death they run... wtf is that?

I like it, but I had to change strategy to survive (sorc, so quite squishy). But now I can do fairly well, rarely die before the boss (even if the tank dies, I can manage to stay alive and still fight with smart use of time, ice and fireball). On some bosses (yes, I'm talking KI elite) I've been the only member to not die, it's not easy, but I've managed to kite that boss (clyde can help) and keep fighting until the tank returns.