How do you guys do it?

How do you guys do it? Seriously...how the hell do you guys do it? I’m 22 and have had a stutter all my life. I aspire to work in investment banking and don’t think that’s ever going to happen. Recently had an interview for a bank...blew it. Looked like I was having a stroke the whole time. Today I had a coffee chat with a potential employer.. couldn’t get a word out and spat when I said something with the P. I go to speech therapy but it’s useless. What do you guys recommend I do? I feel like giving up and don’t know what to do.