I was surprised not to see the roommate suggestion more in this thread.

I guess it's highly dependent on where you're at culturally, as I can think of many regions where this wouldn't be normal.

After ~15 years of living alone I just took on a new roommate myself in my 40s. It's a friend of a family member who is half my age and needed a better living situation. I'm in a house that's too big for me and this kinda works. I'm still adjusting and largely an introvert but this more than scratches my social itch and gives me an excuse to cook more/better food.