I'm so sorry Prayer-Warrior, for what you're going through. I know that for me, these things helped:
1. Cut off as much contact as possible with the ex-spouse. When you talk to him, it just drags you right back to day 1. Keep things politely distant. No chit-chat. Nothing personal. You need distance from him to begin healing.
2. Spend lots of time with family and friends. Have a game night, throw a party, go out to dinner with the girls. Don't stay home alone when the kids are gone if you can help it. Empty house is thinking-about-past-life house.
3. Pray for your ex. Pray for yourself, that you'll be able to forgive him and put it behind you. BEG for this. God will help you if you seek him desperately.
4. Redirect your thoughts when you start picking apart the past. A certain amount of reflection is probably natural and good for our own growth, but questioning everything about your relationship with him... thinking too much about what happened, how you were betrayed, etc, is just feeding the pain. Cut it off as soon as you notice yourself doing it.
5. Try fun new things! You are a free woman! Enjoy it. Go out and do something you've always wanted to do. Redecorate your house. Plant a garden. Find a new hobby. Divert your mind and body with other things.
6. Exercise. Seriously. Not only will your body create endorphins which will make you happier, and release stress and tension and grief, it will make you look even more fabulous and improve your self-confidence.
7. Stick around here and get to know the Singles CC members. They are great about letting you vent, setting you straight, giving you comfort, being good company, helping you understand yourself, and encouraging you to grow in the Lord. So much wonderful!
8. Church participation. Yep. Throw yourself into ministry! How can we dwell on our own heartache when there are children to teach, homeless to feed, meals to cook for shut-ins, and visitors to welcome? Join a small group Bible study. Sign up to volunteer with the children's choir. You will be get to know and love your church family so much more personally, and be blessed abundantly.
Hope this helps some.
Welcome to the forums!