@donduck It might be a personality disorder, if what you describe is true. You may not respond to social cues as most people do. You might want to consider getting a diagnosis from a psychiatrist. If you do have a disorder, they can help you get treatment.
In your case, treatment would include training in how to respond appropriately in social situations. You would learn to identify your a-social behaviors and how to consciously force yourself to do things that other people consider socially acceptable. You would learn to appear nicer and more engaged.
There are classes in these things, and they give you practice in how to behave as other people do. Over time, you become better at it, and because it is hard for you, you will be likely to do a better job of it once you learn how to do it.
Really, it’s just a practical thing. If the current situation really bothers you, I would get evaluated by a psychiatrist. If you can live with things as they are, then I would go on as you are doing. It’s not an easy call. But only you know how unhappy you are and what you want.
If you don’t have health insurance, then you might want to read a book about Aspergers to see if that feels like you. There are a number of books that can help you change your behavior if you decide that is your situation. Or you might find other related conditions that explain your behavior even better. Whatever label you put on it, I think that taking social skills classes will help you.