Boy, I've been through a lot of these situations. Many an hour in the family waiting area and hauling back and forth to the hospital and rehab. Both my late wife and my current wife were extra energetic and able people when I met them, so I wasn't auditioning for a caretaker role, but I think I've learned a little about it.
Without seeming phony, make a point of being upbeat and affirmative with her, and understand she may get depressed in recovery. Maybe collaborate with her on what she'd like for cosmetic purposes while the scar heals --pretty scarves, turtlenecks, etc., once the bandages come off. Of course, give her the say on colors, patterns, design, etc. A paper catalog or online shopping could help.
My wife remembers over time the ice cream and such that I brought her in recovery. Any break from hospital food is excellent, a better grade of coffee, indulgent donuts, candy, etc.
Wishing you both the best. Hospitals are no-smoking zones for sure, so make sure you get long relaxing smokes when you get home, maybe with some music, a beverage, and snack, to keep you going and help you sleep.