Leaving AP

Told my AP of almost 3 years I needed to be done finally. Was meant to be an exit affair for me, just a fling for him, longer we were together the more I wanted from it. I know it’s best in the long run for me to really move on- but how do I get over this feeling of complete shit? My marriage is still a mess and is taking forever to exit.. AP was the only thing I had for myself to feel good about.. how do I refocus and get back on track to be successful in getting out of this slump ? Whole reason I ended was so I could put all that energy in to finding a real next chapter.. but 1 day in and I don’t feel empowered I feel drained and depressed.