Resentment: it can't live in the light

Resentment is typically a self-righteous, one-sided position taken on what was originally a shared, dual experience. It is, therefore, vulnerable to a narcissistic (or self-focused) view of reality. We don't feel resentment toward ourselves (that's remorse), just others. 

Resentment hides out in one's individual version of the past, like a toxic emotional mold resulting from a flood of unprocessed feelings. Typically, working together with your partner to mutually resolve the issue has not occurred. Fortunately, just like with real mold, exposing resentment to the bright light of the present has the potential to neutralize it, kill it off. Talking through an issue with your partner is a holistic approach to healing the pain of continued, isolated holding on.