Welcome back to AB Karmlady, I took some time away myself. I don't think there's much I can add that hasn't already been said. I guess the only thing I can offer is that I'm the same age as you and I got the loneliness down really well too, lol.
Be really careful if you're going to use the Nextdoor app, especially if you put your real name and location (it's a bit like Quora when it comes down to using real names, the users can get funny if you use a nickname). My suggestion, if you're going to use the app, is to use a fake name, one that sounds believable. Be careful if you post any pictures too - make sure that you don't use GPS tagging on your photos (or if you do, make sure to remove the GPS data before uploading).