I can identify with the doubts you're having.
I have massive panic attacks when I try to drive on the highway. I don't know what it is about it, but it never fails. My last job I had to drive the highway alot. I was doing contract type work, and it was jobsite to jobsite all the time. I had many days of panic and general anxiety.
I think you should at least give this new job a try. Don't go in expecting to not be the least bit uncomfortable at first, but trust yourself and know you'll be okay. It's not going to be easy, but I think you need to do it; and I think you can do it.
Good luck, and I know what you're goin through. I'll be rooting for ya.
Dave