Lynne Shallcross, writing for "Counseling Today," says that learning to forgive can lessen hurt and depressive feelings. Shallcross also reports that forgiveness can increase compassion and improve physical symptoms related to harboring anger and resentment, including headaches, stomachaches, back pain and muscle tension. You're not doing your mind or your body any justice by holding on to anger toward a partner who cheated on you. Consider experiencing the benefits of having an abundance of physical energy and vitality and maintaining a positive outlook on past experiences -- hurtful or otherwise -- and future aspirations. Thinking of all that you stand to gain from letting go of anger and resentment gives you the motivation to diligently work toward healing difficult emotions and moving past them.

It's useful to honestly reflect on the circumstances surrounding your partner's decision to cheat -- including your part in the situation -- says the Mayo Clinic website. Ask yourself a few relevant questions to help you gain more insight, such as "Was I honest and sincere with my partner in the relationship, or was I deceptive in some ways?" or "Did I suspect that my partner was cheating but chose to ignore the red flags?" If you try to view the situation objectively and with consideration of your individual role in the relationship, you may realize that your partner's decision to cheat -- although probably not the best choice -- could be attributable to difficulties in the relationship to which the both of you equally contributed. It's not to say your partner's actions were acceptable; the point is that it's important to move beyond placing blame on your partner, which may be keeping you from forgiving him.

Once you've decided to look honestly at your relationship -- accepting both your partner's and your own mistakes -- transition from feeling like a victim to seeing yourself as a victor. So your partner cheated on you: This is a choice your partner made that is completely out of your control. Since you can't control it, it's more effective to try to accept it and move on – this is also where you regain power and control over yourself by not allowing your anger and resentment to take control of your life. It's not to say that you won't still experience anger when you think about your past hurts and the lies surrounding your partner's cheating; you can, however, control how you manage your anger. Instead of holding on for dear life to your angry feelings and replaying any images in your mind that keep you incensed, you can redirect negative thoughts and focus on something more constructive, recommends the American Psychological Association website.

Depending on the severity of your anger and resentful feelings, it may take some time and practice to stop harboring these difficult emotions. You may not be able to completely get rid of your anger and resentment, but you may notice that instead of feeling tension in your stomach and in your shoulders when you think of your partner's betrayal, you have progressed to only experiencing a brief moment of frustration that quickly passes. You may try for months to redirect negative thoughts and focus on more constructive ideas and tasks, only to find that you're even more upset. Try not to be too hard on yourself, and realize that forgiveness takes as long as it takes. If you think you need professional help with healing from the anger and resentment, contact a mental health professional to help you process your thoughts and emotions.