You also have an opportunity to evaluate how you have participated in picking your former relationships. Many times there is a pattern that you follow that is not evident unless you reflect and look for past patterns. These patterns once identified are information you can use in the future to avoid picking partners that match this pattern. You can be grateful for the awareness of your patterns and view it as a gift and blessing for your future life satisfaction.
Many times the grief of divorce is not about the person you are leaving, but rather the loss of the idealized family life you wanted. For lots of reasons, many people long for a "traditional marriage" with a mom, dad, and kids that live "happily ever after." The realization that this is a dream that will not be happening is devastating.
Turn the devastated feeling into an opportunity to be grateful for living in the reality of your life. Your eyes are open and you are aware of what is, not what you hoped it would be. Optimum mental health is the ability to stay in the present moment and holding onto reality at all costs.
Believe you can heal from your divorce. Harboring hurt, resentment and anger for long periods of time only hurt you. Your ex is not harmed at all by your resentment. So do yourself a favor and nurture an attitude of gratitude for everything however small. You deserve to thrive as a newly single person.