I just want to add that no matter how bad it seems now, this is an anxiety that is possible to eventually defeat.

I was terrified of driving when I was young. I never wanted to learn, so I had to be forced to. But now, 10 years later (I'm not saying it's necessarily going to take that long) I regularly drive on a major highway between two fairly good sized cities. I mean, it's not LA or Chicago, but it IS a major multi-lane highway with quite a bit of traffic going 80mph give or take.

So, my point is, if I can do it, so can you and anybody else. You just have to get out there and do it. Work yourself up to it. Figure out what makes you so anxious. For example, I had a lot of anxiety about getting lost and not knowing where I am, so I got a GPS, now I pretty much always know where I am.