How do I stop stuttering

How do I stop stuttering I'm 21, I've been stuttering ever since I was in kindergarten and have been beaten by my family and others because of it. When I was in highschool it started to get better to where one could hardly tell however every now and then I find that no matter how hard I try just can't make a sound come out, with other people it's easy enough to write off but there are times where I start to overthink and in the end I just go back to not being able to say a single coherent word. I just want to know if this happens to anybody else, I just thought after all this time it would stop.