I knew my friend's partner was cheating. So this is what I did.

 I promised my friend I’d always tell her the truth, but I just couldn’t tell her this.

When I found out my best friend’s partner was cheating on her, I was devastated.

A mutual friend had spotted him with a girl at a beach and they were clearly romantically involved. It took her days to tell me about it and I just knew it was true. Because my best friend and I had been having conversations about her relationship. She felt something was off. Instead of getting engaged after dating for three years, he had become distant and was finding excuses to spend less time with her.

The thought of having to tell her was so upsetting. We had always sworn we would never keep anything from each other and we’d had conversations about these situations. “I’d totally tell you,” I’d say and she’d agree. We’d always tell each other the truth about everything, no matter how painful.

"I didn't want to be the one to tell her he was cheating."

But I didn't want to be the one to deliver what would probably turn out to be the most devastating news she'd ever received so far in her life. And I hated him for putting me in that position.

I found myself wanting to talk to him, not her, which technically was a betrayal of my friendship with her, but I needed to know if it was a serious affair, if he still loved my friend, if the affair was still going and if it was over.

So I confronted him.

"I know you're cheating. Don't deny it. Someone saw you two together  and I had a feeling you were. Just tell me if it's still going on."

"No, I swear, it's over," he said, shocked into telling the truth.

"Good. I'll give you 24 hours to confess and if you don't tell her by Saturday, I will tell her myself. It will be better coming from you."

Then I walked off, leaving it in his hands. He told her that night and she came to me for comfort. I was happy to be there for her. I didn't want to be the bearer of bad news, I just wanted to be her friend and be there for her as much as she needed me to be.

It took months but they managed to repair their relationship.  Nine years later, they are still together, and yes, we are still friends.

It was so awkward between her partner and I for so long but because she had no idea, I got to keep my best friend. If I had been the one to tell her, and they'd stayed together, I have no doubt our friendship would have suffered.

Would you tell your friend if you found out her partner was cheating?

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