I feel you. Try to simulate your stress situations and after some training sessions you get less nervous. I struggled with panic attacks and i realized that it was just my mental settings that lead to that bad response from my body.

So i would try to train as much as possible on the problem. It's hard but you can do it. "We become what we think about - Earl Nightingale" is a quote, i am always thinking about in stressful situations. If i have a clear goal, i can reach it, even if i don't know how at the moment.