Forgiveness allows you to move past judgment into understanding and even compassion or empathy. It allows you to take back control over your emotions and to take responsibility for how you're feeling in any given moment.
I became curious about Conor and how he used the Law of Attraction to manifest his status as an infamous UFC Champion. What I learned (which closely paralleled the teachings in "The Secret") was that our thoughts hold some sort of mystical power/energy.
Emotions are not the cause of your suffering. Your thoughts behind the emotions are what cause the uncomfortable and often painful feelings. Your emotions are the result of your beliefs about those thoughts.
"People often think depression is just being sad all the time, but it's far more than that. In fact, people with depression do not necessarily feel sad - they often feel numb, like an emptiness where emotion should be."