Aurora, I am battling the same loneliness you are. There are things I can do to fill up my day, but in the end, I come back to an empty house. And some days there is nothing on my agenda or I just don't feel like leaving. I never thought I would consider 55+ housing, but it's starting to sound good to me. Someone suggested I find a roomate, but I also like my own space.
I talked to a woman who mentioned she and her friend bought a duplex together. I happen to have one, but no friend who needs a home.
...just want you to know you are not the only one. There must be a lot of us out there. But I think there are a lot who like to be alone.