Never good news, even when it's good

Even though things are going well in regards to the tumor my mom still acts defeated. She had the drainage tube removed because the tumor has stopped producing fluid. This is a good thing. She is in pain, thinking the tube left scar tissue around her nerve. She hurts and has blood pressure problems. Now we deal with her pain, anger and disappointment. Nothing seems to make her happy so interacting with her is hard. I watch my dad becoming bitter that she is not pulling through this but I can't say I wouldn't withdraw if it were me. You never know. They both believe deep down that she's dying, mom and dad have both made statements to the fact that she's "a dying woman" at one time or another. Never around each other of course. As a daughter this hits you in the gut and is hard to recover from. Even in correcting them I can see they believe it. I and my sisters remain optimistic, hearing the Drs good news and latching onto it. We talk about moms negativity and how to change it. The fact is, we can't.