I think sleeping apart during the first part of this recovery is almost a requirement. When both people are getting little sleep, then no one's wide awake and cheerful, which is a recipe for short tempers and arguments. This is a time when the patient really needs a helper who has an unlimited supply of patience, and if they're not well rested, the last thing they'll have is patience.
I know from experience that a lack of sleep causes short tempers, grumpiness, no patience, etc. I have a husband who snores like a jet engine. I was getting little sleep every night; what sleep I did get was constantly interrupted by the jet taking off and I was frustrated beyond belief constantly, and totally exhausted. I am generally a cheerful and patient person, but that went out the window when I wasn't getting the sleep I needed every night. Some years ago, I finally had to realize it was okay to buck society norms and expectations and move to separate bedrooms. I ignored what some people thought, and said, and now I enjoy my nightly peaceful and uninterrupted sleep, not to mention I don't feel like smothering him any more. I'm also a night owl, and hubby is usually in bed several hours before me. I had to try to sneak into the bed without waking him, which was a pain at best. Plus, he gets up at the crack of dawn raring to go, while I'm still sound asleep. The noise and light woke me every morning and it was hard to go back to sleep. I've come to the conclusion that couples sleeping in the same bed every night can be overrated and is not always a good thing for everyone! And, when necessary, even if it's a temporary solution, it's the perfect solution for when one partner is having sleepless nights and the other one still needs to sleep and be well rested.