Of COURSE you can cry - just wait until after the door is closed. You want the babes to see you smiling and waving, telling them that they are going to have a great time!
Arrange for one or two of your girlfriends to swoop in and pick you up within 15 minutes of the kids going, then go out and cut a rug. Or scrapbook. Or bellydance (I love that one!). Or hit a comedy club. Or a movie. Or an all-male review! Hey, treat it like the Bachelorette party you never had!
I even did a few "slumber parties" with my few single girlfriends, so as to ease into being in the house on my own.
As far as the business end...it sucks that we have to do most, if not all, of the leg work for something that we never wanted. But remember that you DO want to get the best, fair outcome of what is rolling your way, so keep all those ducks in a row. Strangely, I was able to keep that separate from my emotions, mostly. Made him crazy that I was all business when it came to the legal stuff.