JUst FYI though LC- D's wife is the number one most likely to be seriously mentally ill/drug addicted WAS on the boards (and I've been here a long time and seen it all).
This generous description of factors that D laid out may be triggering your wife is certainly likely. On the other hand, if she's a narcissist, some narcissists (the sociopathic kind) would simply bow out of seeing dying relatives in the hospital because they don't like it and they don't want to do something they don't care to do. (My exH was not a sociopathic narcissist, but more of an insecure narcissist - he really really cared how he looked to others, and by extension, how his wife and kids made him look to other people. He would go see the dying relative so long as other people were going to see it, so he could play the big man. But privately he lacks empathy for the troubles his adult kids are going through, griped endlessly about it when we helped my younger brother out of a jam that was not his fault, etc. Publicly he's the great humanitarian but privately - not so much.)
Only you know, if you look back, if this was a pattern before the crisis of her only doing the things that she enjoyed, and bowing out of things you might have wanted to do. Or bowing out of things that might have required her to put herself out for other people. If any of this resonates you might want to read The Sociopath Next Door - quick and easy read.
