sorry you gotta go thru this, but you're right...we've all been there at one point.
I can only offer a few thoughts.
first off, you will land on your feet, rest assured.
second, I feel that's it's a common flaw to think/worry about how you'll ever replace her. that was the very first concern I had a few years ago I was in the same spot. took me a while to get grounded, but then the sky cleared and I found myself much more confidant then ever before.

a tip: I asked my 10 year old daughter how I would ever replace my lost love, and she gave me this advise.

"it's simple dad, just find a pretty girl, walk up to her and say "if you were a booger, I'd pick you first."

I hope tomorrow you'll wake up and see that there is a fresh new year ahead of you.