The worst part of sinus surgery for me was right when I got out of surgery, I was so drugged and I was vomiting blood that was dripping down from my sinuses. People say you won't be hungry as soon as you get out of surgery, but I was starving. Thankfully, my boyfriend brought me a milkshake, I recommend your wife bringing one, too. It tasted amazing and filled me up. OF course have someone drive you home. I was really out of it and so having more than one person to walk me to the car and get me out of the car was helpful, but not necessary.
The first 24 hours post-surgery is when you need the most care and to have someone there to watch you to make sure you don't start bleeding too much and to help you with basic needs. I didn't feel like moving and was scared to move my head around too much, so my sister's job was to just switch my gauze, and bring me water and food. She also helped walk me to the bathroom. You pretty much need to sleep upright otherwise blood and mucus will drip down into your lungs. After the first 24 hours I don't think I had constant care. I just slept the whole time because of the pain meds. After 2-3 days I stopped taking the pain meds and felt a lot better. I think the pain meds were making me feel worse than I was really feeling, so the earlier you stop taking them, the better.
The aftercare wasn't too bad, I don't think your wife will need someone else to assist unless she needs to leave the house in the first 24 hours.
Good luck! My sinsuses felt great after the surgery(especially when they took the gauze out from my nose).