Sorry. It can be hard sometimes. I used to struggle with that too (and still do now). Something that helped me was just trying to get into more hobbies/groups, though it can be hard when you're an adult.
You'll probably be ignored in those things at the start, but over time you might build more friendships. When I entered my current university club, I felt pretty lonely; didn't really know anyone there, and they already were friends, had their own culture etc.
But over time, I started doing more things with them, I tried to volunteer when people needed help, went with them to get lunch/eat and so on. Nowadays we are pretty cool with each other. And I have a pretty loner personality, you might have more success than me if you try.