I am sorry M.......I can tell you from my experience that every step gets a little easier. When my x told me she wanted to move forward with D I felt the same way. I took another mental hit when she told me she was dating. It happened again when she told me about her BF and yet again when he met my girls. When our D was finalized I stood in front of the judge and cried. I can tell you though that was the last time and every step since then has got a little easier. I have felt gloomy days as well and have my share of times being in a funk. I just keep telling myself that something good has to come of this and it will present itself when the time is right.
Not that any of this helps just know that what you are feeling is completely normal and your time will come. Just be compassionate towards yourself.