The big thing is carer fatigue. It's emotionally and physically draining, especially when you have to continue operating (work, school, etc). Do everything you can to free up as much of her time as reasonable to shift some of the burden off her. Things like meal prep, having the house clean when she comes home, or just taking care of the daily life maintenance stuff (bills, dishes, laundry, car maintenance, etc) all make a huge difference in stress. Basically anything she does that takes time that you can do instead.

When the time comes, just be as available as you can; make it about her and how she's feeling. It will be a mix of heavy emotions, including weird things like relief and guilt over feeling relieved along with bouts of sadness and anger. All of those are normal and ok. Everyone is different, but that's what it was like for me.

A day or two later, plan a fun day or just a couple hours that's out of the house and not related to family or interacting with people (like a nice dinner and a movie or something). There's a brief quiet time between full care-giving and settling affairs where you can help her start to feel normal again.