My dating days go back 40 years (I understand things may be quite a bit different today), but Friend's invitation sounded very strange to me. I had close male friends too, but there would be only two situations where I'd have invited any of them to spend the night: (1) They had drunk too much alcohol to drive home safely or (2) They were from out of town and just needed a place to crash.
It sounds like this Friend is also the Ex from previous threads. (Ex had cerebral palsy, and Friend is on disability. Sounds like the same person.) If I were the OP, I'd have been pretty suspicious that this was an attempt by Ex to get back together with Boyfriend. Hang a few decorations, dinner, movie, stay over, breakfast -- I'd call that more of a date than hanging out with a friend.