Hi!
I am an NT mom of an Aspie teenager (won't move out for three years, but I have older children who have moved away), so I kind of know what you're feeling.
Do you belong to a church of some sort? That can be a bigger community of people you can socialize with to a degree. Also, is there some sort of gardening and/or construction group that you can meet up with? Or start going to a class on one of those subjects? My hobby is knitting, and I know that when the last child leaves, I will force myself to go find a knitting group to keep me from getting lonely or too insular.
Also, I've always thought that I would go volunteer for Habitat For Humanity when all the kids are gone -- get outdoors, do some heavy labor, learn some new construction/renovation skills. That might be a good opportunity for you to meet people AND do something you are already interested in.