I'm 28 and also have no friends but mainly because of my christian beliefs people turn away but I do also stutter. It must be tough for you though especially while at a university. My advice is to open up about stuttering but know your limits. Don't force yourself because it becomes worse when you do that. I would start small by adjusting your thought pattern. If you get embarrassed and start to have thoughts about isolation or something similar try to make adjustments like "well that was embarrassing but I'll manage and continue on, it's not the end.." your thoughts can beat you down also so just make small adjustment. You're not alone there's alot of us stutters out here