I'm not a professional, but I'm pretty sure depression can have an impact on stuttering. I know anxiety causes stuttering for a lot of people. It seems like they would be directly related. I've always hated talking about it too. When I don't think about me stuttering, I usually don't. I know it's the same for a lot of people. Talking about it with anyone helps out a lot. It even could help with stress and depression. You definitely shouldn't be embarrassed when talking to a speech therapist. They deal with this stuff everyday. They won't judge you, they're here to help.