C-Q, I'm so sorry, I don't know the full situation so my thoughts may not be very appropriate. But I've often thought about how I would approach a terminal illness (and I'm not sure if your DP's cancer is terminal or fight-able).

I guess, to a certain extent, it comes down to choices. I would feel conflicted if I had a terminal illness if I wasn't sure whether to keep fighting or whether to accept death. For someone who has always been afraid of death, like me, that would be mighty difficult even if I felt there was no hope. But I would hope to get to a place where I accepted the situation for whatever it was.

It sounds like your DP needs to find some peace and some approach that is manageable for him. That might be to accept that what he is facing is really difficult but still worth fighting and that might be to accept his own mortality, try to make his last days happy.