The more she can get up and walk the sooner the healing. I'm sure the chemotherapy doesn't help w/her energy levels but there is danger too in constant bed rest. Her muscles are going to atrophy w/o enough activity and exercise. I do NOT mean she needs to exercise tho. In her condition I'm sure just gentle walking around the house to build up her strength and protect those muscles from atrophying will also help w/the healing. Encourage her to walk as much as she can. Walking should help more stool move thru faster so that the need to go becomes less frequent and more BM is passed w/each movement.
Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.