There is a company called Spa Where You Are (www.spawhereyouare.com). I received a gift card for a pedicure while I was on bedrest during my first pregnancy.
I never used it through (shame on me, I know!!) but my baby was born early and then I had a premie newborn and we bought a house when he was 4 weeks old and blah blah blah.
Anyway, they'll come to her house and do the services and maybe if you brought lunch or dinner and did them side by side, it'd be a nice treat for the two of you and you could catch up.
I would double check though because after a heart surgery I know many people need an antibiotic before going to the dentist and I don't know if the same applies to spa treatments (my guess is that it's because of bacterias introduced to the body and the heart's inability to fend off infection.)
If that won't work, once she's home, maybe a gift certificate to Netflix? That way she can order and have the movies delivered and picked up from her house. Or offer to clean her house and do laundry once a week? Or hire a company who can do it if she's not comfortable with friends washing her skivies.
Time with her will be the most important thing though and I agree with another poster to get a schedule going. There is nothing like the long, drawn out days of being stuck at home while the rest of the world is going on around you. It can really suck.
Good luck and you're a good friend for wanting to do something different!