I can’t tell you how many times I had ended up with little to no blankets after sleeping 4 four hours. Eventually, spouse and I decided that we would get two full-size blankets for the bed so that we could each have one. This has prevented so many restless nights.
I think it’s perfectly reasonable to sleep in separate beds. Just because you don’t sleep next to them doesn’t mean you don’t enjoy their company. Whenever my girlfriend would come over I’d wait until she fell asleep and then go sleep on the couch. It was an understanding we had. She fell asleep better with someone there and I fell asleep better by myself.