Increased from $1800 to $1837 at this moment, I'm an idiot because I sold everything I had at $1790 expecting another correction down to $1600.
Now I regret my poor decision and despite all of my own advice I've done what I've always told others not to do

If price drops down back to $1200 I might first have a heart attack and then throw a party if I'm in the mood.
I was just thinking about Satoshi and realized even after all of us gone bitcoin is going to be here, that's something I'd like to leave behind when I die.
It's a rookie mistake, but glad you at least realize that you have done wrong. As is the case with never buying all at once, you should also never sell all at once. The trick is to cash out max 15-20% of your profits. If the price happens to go up, which is exactly the case right now, you would be able to cash out another portion at these higher levels. I am not sure whether or not we'll see a dump to the $1200 level, but you'll surely get the opportunity to buy back at lower levels -- have patience.
That is what I'm saying. That I'm hoping that people who have sold won't regret their decision. But for you the situation that is unavoidable. Because you already saw big profits that's why you jump.
But selling all of you bitcoin is really a big no. You should gradually off hold your bitcoin as there is a increase and decrease of price so that you can fully maximize if the price rose and minimize your lose if the price dip. Just learn from your bitcoin and not be frustrated and go back to buying bitcoins if you still can.