I am deeply moved by your situation and understand the devastation following a desertion. Trying to understand his motivation and lack of caring re-injures you emotionally. No matter how many times you try to understand this story of betrayal it will leave you empty. This is a time to reclaim yourself and reconnect with those who love you — and whose care can fill you up. Building a network of social support takes some doing. Asking for help, expressing gratitude toward those who have extended their kindness, and immersing in the best self-care practices you can will help you feel better.
Thoughts determine the direction of our feelings and behavior. If you dwell on him you are turning your thoughts toward more difficult and unsatisfying feelings. Focusing on what you need and the loving people in your life will be better way to go.
Wishing you patience and peace,
Proof Positive Blog @ PsychCentral