I am a master at self-sabotage, but managed to get my PhD. I also went through a divorce during my grad program. What I had to do was clearly identify my goal: finish the PhD. It seemed overwhelming, so I then wrote down everything that needed to be done to complete. I then broke this down into small steps, steps as small as weekly or daily work. Each day there was something to do, even as simple as spending hours photocopying journal articles (showing my age here). Making sure everything was properly formatted was a huge task, so get a head start on that as well. The best piece of advice I received was being told that my professors are waiting for me to know I am ready and finished. They will always suggest another article, a weakness, a needed change...what they wanted from me was to declare it finished it that it was time to defend it. I did that and they just said OK and scheduled the defense.
The key, though, was to break it up into small steps so there was something to do each day but not get overwhelmed. Good luck! You will feel an enormous sense of freedom when you turn it in for the final time.