I have this problem and in my case it started before I moved to United States. I went to same school when I was a kid until age of 12. Then I went to a private high school in a different town where studied for 5 years and it felt like I made a lot of friends there. After that I went to college in a different country and studied there for 6 years where I also made a ton of friends. Then in my mid twenties I moved to United States and initially it felt like I had made a lot of friends during my first few years in the States but pretty much nobody from my college or high school years were in touch with me by then. After I got married, it felt like I lost most of my friends that I had made. Being married was very lonely and I got divorced and moved to another state. I worked at different places and had normal relationships with people but after I switch jobs I noticed that nobody stays in touch. I'm getting closer to my 40s and I am thinking a lot about this problem that apparently I have but I can't point out what am I doing wrong. I am not rude to anyone and don't have bad habits or other negative things that are obvious to me but I do wonder what is the cause of this.