I'm 37 and can relate to this. I lived and worked in another country for a pretty long time and was forced to move back home due to layoffs. I dont really know anybody apart from my family members any longer because I was away for so long. I don't feel bad about it all the time but there are days when I too feel hollow and long for some social life. I don't have a lot of answers, traveling has helped me to connect with other travelers a bit, that's one thing.