I thought I would feel elated to finally be done (our process took over two years to reach finalization) but instead I was really sad. I had booked a vacation the following weekend with my now-husband to celebrate but instead spent a good portion of the weekend crying or being overly sensitive. It didn't help that we had booked ourselves at a total "party" hotel, that was my fault.
In retrospect, leaving my marriage was the best thing I could have done for myself and for my kids - but in the moment, I experienced that second-guessing about whether I had made a mistake.
Sharing just in case you thought that the sadness you are feeling is any sort of sign of anything but what it is - a normal part of ending something you had hoped would last forever. Take care of yourself. It took me a week or two to process.