Crippling anxiety/writer's block writing ANY thing - including emails

Hey guys,

You might be the right crowd for this. Roughly ten or fifteen years ago (as a teenager) I developed this horrible writing block (phobia?) toward creative fiction, and I haven't really been able to do it since. Even worse, lately this has manifested into the inability to write anything at all without freaking out, including emails or things for work (I actually got fired more or less for this but that's a different story).

It's like my writer's block is so bad that when an email I'm trying to write doesn't come out exactly like I want it to I'll flip. I sent an email out a half hour ago and I'm still beyond tense from it.

Does anyone here have experience battling writer's block? I'm assuming I have stage four at this point. Any help (even just positive stories!!) is appreciated very much. I just think that you guys might know best. Thank you.