I posted on here a few weeks before mine was final (June 5th). While it may seem like the end of the world to you now and you want to do whatever you can to make things better, sometimes there just isn't anything that can be done and one person trying to make it work will never get the job done if the other has already moved on. Not saying you shouldn't have a serious conversation and see if there's a chance to work things out, but don't lose yourself or get stuck in what might have been.
Despite having been separated for an extended period of time, the actual court proceeding was gut wrenching for both of us even though it only lasted 10-15 minutes. Lots of emotions at the end of 12 years together. But, its only been final two weeks and it just struck me yesterday that there is a night and day difference in the stress in my life. I wavered many times over whether or not this was the right path but in the end I think it was the only path for us.
Hang in there and take care of yourself. The stress will eat you up if you let it.