Give Jack a break! He,s just lost the love of his life and had to sacrifice his own granson to save the planet. His daughter's not speaking to him and he's had no time to mourn the other two team memebers he lost a while ago.

and now the Doctor's soon to regenerate which is a sort of death. how much more can one man, even an immortal take? No wonder he's going dark. Everyone he lovea is leaving him in one way or another.