The researchers in the study found that if people were very forgiving of themselves and others, that alone completely eliminated the connection between stress and mental illness.

"It's almost entirely erased — it's statistically zero," "If you don't have forgiving tendencies, you feel the raw effects of stress in an unmitigated way. You don't have a buffer against that stress."

Reflect on the hurtful events, and really think about how the anger and hurt it caused you has affected you since. A real eye-opener.

Empathize with the one who hurt you. Try to see where your horrible ex-boyfriend was coming from when he wronged you. We're not saying he was right, of course, but give the situation some context.

Forgive completely. This may be hard, but forgiving someone even if they never apologized is critical here. Remember Eva, the Holocaust survivor? Let your forgiveness come from a place that understands no one is perfect, not a place that just wants to end the beef for the sake of it.

Ditch expectations. Your ex-boyfriend may not ever apologize, so don't expect it. You don't need to wait for him — or anyone — in order to clear your own head of anger and hurt.

Forgive yourself. If someone wrongs you, know that it is not a reflection of your self-worth, Swartz concludes. Just do you, because you rock. That includes forgiving yourself.