Man walks in on cheating partner days after beating stage 4 cancer

A British cancer survivor says he almost took his life after learning his partner had been cheating on him while he was battling the disease.

Speaking to My London, Tom Garrod, 44, said the discovery of his partner's infidelity "felt worse" than getting his diagnosis of stage four testicular cancer in 2004.

Garrod was initially told by doctors he had three days to live when he was diagnosed, but eager to conquer the disease, he pushed through.

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Garrod went through an exhaustive treatment process of chemotherapy and steroids to recover, and when he finally got to the point of being cancer-free, life threw a new obstacle at him.

Returning home a day early from hospital, Garrod opened the door to find his partner cheating on him with another man.

"I just felt so shocked. I honestly felt worse being cheated on than I did when I got my cancer diagnosis," he said. "I found out it had been happening the whole time."

The survivor said even though cancer had been such a challenge, it was heartbreak that really got the better of him.

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"The cancer was out of my control, but with this, I kept thinking, 'Was it me? Did I do something wrong?'"

Garrod tells My London the shock spiralled him into a deep depression, and he began to smoke and drink. During this period he felt there was no way out — until something "clicked".

Realising "enough was enough", he started investing his time, anger and energy into exercise and living a healthy lifestyle.

Garrod even ran from one side of Wales to the other — an equivalent of 814km, to raise money for Kings College Hospital, London.

In an Instagram post, Garrod said the challenge was "the hardest thing I have ever done".

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"I've been raising awareness for [testicular cancer] and its early detection...by running ultramarathons reaching distances as for as 506 miles (814km)," Garrod explains in a post.

"If you are going through cancer or have recently been diagnosed, just remember this: NEVER NEVER GIVE UP ON YOUR LIFE, IT'S WORTH FIGHTING FOR."