Warlock, I know exactly what you mean about the constant lack of concentration and always wanting to erase something moments after you've written it. I am too sick of this endless regretting of all the times when I deviate from my typical social phobic behaviour, like speak out more than I tend to usually, or post something online that is my own opinion. And that's really ironic, considering how I should be proud of myself for refusing my social phobia take over my whole personality.
I used to attribute these racing thoughts disabling me to concentrate to ADD, but I guess they're there due to my anxiety mainly. The avoidance comes in when you don't even bother to read a book or write something because you dread facing regret again. But like you said anything beats feeling this emptiness... Regret is still better than emptiness, right?