My eyes were so blurred with tears, I could barely read the text on the computer screen. I was checking the final corrections to my husband’s latest book. A tear dripped onto my handwritten notes, smudging the ink. Our office manager sat beside me. I blew my nose and told him I was suffering from terrible pollen allergies.He was probably already aware of my husband’s philandering.

I reckon I was the last one to know. I had just found out from a damning text message on my husband’s phone. What a cliché! It was excruciating. I’d even written a glowing forward to this latest book, praising him as a loving husband. I’d written that after our 25th wedding anniversary when I thought we were closer than ever before. Little did I know that only a couple of months later, my world would come crashing down when I found out about his mistress, whom he refused to give up. Yet I still thought my husband and I had a future together. He was the love of my life, the father of my kids. I really wanted to be able to forgive him.

When I called him out about the infidelity, my husband offered me a part-time wife position. “I’m perfectly capable of loving two women at once” he declared. “I’d be happy spending two or three days a week with her and the rest of the week with you.”

I actually considered his proposal for several months, trying to get my head around it. Could I make my husband be more loving towards me if I agreed to him seeing her as well as me? He insisted it was just my conditioning that made me balk at the idea, but I worried that my husband wanted her for love and passion and only needed me around to do the taxes.

Then I was diagnosed with breast cancer for the second time. I carried the dreaded BRCA gene that Angelina Jolie had believed to be a death sentence. It was a double whammy that left me reeling.

While I was going through chemotherapy, my husband was at a resort in Europe with his girlfriend. Sitting in a chair at the clinic with an IV hookup in my arm, dripping chemicals into my veins, I felt an aching void. It was obvious I could never stomach a part-time husband. I had to let him go. Yet for my own peace of mind, for my sanity, for my health, I needed to forgive both him and the young woman who was his mistress. Hanging on to resentment was just draining my energy—the last thing I needed undergoing cancer treatment. I wasn’t going to let him treat me like a doormat, I had to put myself first, but I knew I needed to forgive him, truly forgive him, to break the emotional hold he had on me.

If I could wave a magic wand and make the cancer and infidelity never have happened, I would say, “No thank you.” I don’t regret having gone through the experience, bleak and difficult though it was. I’m actually grateful to my now ex-husband and his girlfriend. Forgiving them means that they don’t occupy valuable real estate in my head. I’ve got so much better things to think about these days. I used to help my husband produce his books. Now I write my own books about infidelity. Regret is not about the past. It’s about the present and I’m perfectly happy with my life as it is right now.

When we discover our partner’s been cheating, it’s so easy to fall into the trap of playing a blame game and plotting vengeance. Revenge is the opposite of forgiveness. Forgiveness allows us to move on and reclaim joy in our lives. The best revenge is to get past the need for it.

CJ Grace  is sharing a slightly abridged version of this story in a Speaker Slam Inspirational Speaking Competition on the theme of forgiveness. Watch her speech on YouTube and please like and comment.