People at office treat me like I'm stupid & slow, and they laugh behind my back

People at office treat me like I'm stupid & slow, and they laugh behind my back Hi there, So, I obviously stutter that's why I'm here. I work from office as Software engineer. Have noticed that some of my co-workers treat me like I'm a freak, just because I stutter & stay quite. Some of them even laugh with others, pretending it to be about something else. They do that, because they think won't be able to catch them doing so. Apparently, I must be a dumbass, that's why I can't communicate to save my life. Nobody invites me for anything. People look at me with weird eyes. Feels like I exist to nobody, like I'm not even human, but some useless random object, whose only purpose is to do my job - programming. Why do they think that it's my fault that I find communication to be uncomfortable? And why is it my fault that I can't talk fluently like them? And almost all of them are graduated from prestigious universities + have worked at popular tech companies. So, it's not like they're inexperienced in professional environment. Not sure what I can do here. I don't talk about stuttering with anyone, even my family. So, please don't suggest me to talk with my manager, because that wouldn't help. The main issue will still be there. Other than stuttering, I don't have much social skills, and feel lonely all the time.