Some things that helped me: Live in the present. If you find yourself ruiminating about him, the relationship, his wife, etc...STOP. Focus on the smells, sounds, etc around you. Realize that all the crying, feeling awful in the world doesn't change it.
Resolve to journal daily. Try not to talk to all your support system about it. They are tired of watching you go through this.
Getting the journey from abandonment to healing. Excellent book that truly helps.
Make a "favorites" list...things you like to do. Mine are watching mindless TV and baths. Be good to yourself.
Block his phone number. This prevents you from obscessing about his contact.
Envision a life without the chaos. What will it look like? What did your life look like before him?
Remember you only have to get through today and do the right thing for you.