First I wanna say please don’t commit suicide. You have so much in this world even if you can’t see it now. I know stuttering sucks, but you’re young, you have a lot of time to turn your life around. It won’t be easy, but that’s just how it is for us stutterers. I would try to give you advice, but considering you have been to speech therapy for years, I’m not sure I could do better than them. Have you ever tried cursing? You could always try the Samuel L. Jackson, whenever you feel a block just curse. You might be cursing a lot, but if it helped you talk I think it would be worth it. Maybe you could even inform employers so they know why you would curse so much in a job interview? Of course this is assuming you don’t stutter when you curse