Fallout from Internet arguments

What happened yesterday has brought up one problem I have with Internet arguments that I really wish I could change about myself.  Yet it always seems to pop up even when I try very hard not to let it get to me.

And before I say what that is, I want it to be clear that not all of what I say below is about yesterday.  It's about any argument/discussion/debate that I get into online, where the feedback is not immediate.  This was just prompted by yesterday.

In any argument/debate on the Internet, unless it's in a chat room (in which case, it's the same as if you're speaking, as far my problem is concerned, because the interaction is "real time"), typically it can be minutes, hours, or even a days before the person you're discussing things with is able to respond to what you said.  I have this tendency, and it's something I do on a lot of things, not just discussions, to stew on it in my brain.  To go over and over what was said, what I said, previous responses if this isn't the beginning of the argument, and try to think about what I might have said differently.

That's all well and good, except for the fact that I do it *way* too much, rather than just thinking about it for a bit, and then leaving it until the person responds.  No, I definitely stew.

But what's worse is that I start extrapolating from the point I'm at in the discussion.  I start thinking "what's he/she going to say next?" and then mentally preparing for it.  In cases like yesterday, the responses can only be two things:  positive/accepting or negative.  Yes, the details can differ wildly ("Positive" can range anywhere from "You're right!" to "We'll have to agree to disagree, but I still like you.").  But in general, it's just those two things.

A positive response is great!  That way, we're all on the same page, or at least accepting of our differences and able to move on.  Unfortunately, that doesn't take much preliminary brain power, and thus I don't stew on that response very long.

No, I stew on the possible negative responses, the potential "How could you even think Obama's wrong, you asshole!" or "The Flames are overrated? How can a total loser like you even make any kind of coherent hockey point?" answers tumble over each other in my mind (though obviously those wouldn't be from the same argument).  And then I start formulating my response to these hypothetical responses, getting a bit angry or stressed as my different responses jumble with the other person's potential responses, all congealing into a mish-mash of heated words and ended friendships that have their origins in something that hasn't even been said yet!  And probably never will, as most people are a lot more diplomatic in discussions than what goes off in my imagination.

I also have to say that this doesn't say anything about my opinion of the person I'm discussing things with, as this happens whether the other person is a complete asshole or whether it's somebody who I love dearly but just happen to be on opposite sides of the issue about.  It almost becomes faceless in my head at this point.

As time elapses and there isn't a response, that feeling does eventually go away.  It's most intense right after I've posted my response.  But it's something I would really like to change about myself, and I'm working on doing that.  I don't need something like that adding to my stress.  And I wish I could get rid of that general "stewing" thing completely.  But baby steps.

Now do you see why I don't like discussions that are likely to get heated?