I am stressed out by groups of people and have some (not crippling) social anxiety. I tend to come home right after work as it's my happy place. I don't see the appeal of bars, libraries, etc as a Place To Be because I have my home (which is a privilege I am thrilled to be able to have) and bought one so that I can be there instead of out in an environment that isn't mine.
I do have a virtual third place if that counts - it's a Discord server. The people there are friendly and I can always lurk or leave if I don't want to socialise.