My husband and I were excited as the cruise ship pulled into its final stop, a small port in Mexico, in April 2016. Ryan and I ​had been zip lining before, so when we saw signs for an ecopark boasting 11 lines in the middle of the jungle, we thought, “Let’s go for it.”

We got off the ship at 8am and had to be back by 5pm. We’re avid cruisers, so we knew activities were much cheaper to buy at the port than onboard. By 10.30am, we were admiring the view from a high platform, waiting to cross the deep gorge by zip line – a distance of 2,100ft. Ryan went first. It took about a minute for him to cross. Then it was my turn. I’m petite, at 5ft 3in and 120lb, so wasn’t worried about putting much strain on the line. I felt safe: I was wearing a harness and helmet. The guide said, “Have fun!” and sent me out.

I was 500ft up in the air, enjoying the beautiful view of the ocean to the left and the rainforest below. The first I knew that something had gone wrong was an eerie silence. Until then, there was the high-pitched zinging of the zip line. All of a sudden, it stopped. I was halfway across the gorge and began falling in slow motion for what felt like an eternity.

After several seconds, I felt a jolt and heard rustling. Then there was a hard yank. When I opened my eyes, I was upside down. The handlebars of the zip line had caught in the V of a tree branch. That broke my fall, but my body flipped backwards and I was hanging 40ft from the ground with my feet above my head. I could hear a branch snap. That terrified me. I thought, if I fall the rest of the way, I’ll die.

I was wearing shorts, a vest and flipflops, and I was covered in blood. Soon, huge ants and spiders were crawling on me. I screamed for help. Ryan was waiting for me on the landing platform when he heard a loud noise and saw the metal cable slip past his foot and disappear. “What the hell just happened?” he said, but the guide had no idea. Ryan was so relieved when he heard me screaming, though he couldn’t know if I was impaled on a branch or paralysed. He went down the mountain, ripping through the bushes, following the sound of my voice.

When he reached me, I kept repeating, “Please, baby, catch me if I fall.” My leg was split open. My left shin was the size of an orange. There were huge abrasions on my right leg from where the metal cables had zipped through my skin – I don’t know how they didn’t cut my legs off. My right buttock was cut open and dripping blood on to Ryan below.

Nobody knew how to get me down. After 20 minutes, they loosened the tension at the end of the zip line, which was still attached to the base platform. I had to turn the handlebar sideways, to release myself. I knew Ryan would catch me.

Back at the base, an ambulance was called and the guides tried to feed me tequila, which I didn’t want. At the clinic, they took x-rays and brought in a surgeon. I didn’t want surgery, though, as nothing was broken. I knew the ship would be leaving at 5pm and didn’t want to be left behind, especially as our passports were onboard.

I had to convince the crew to let me back on, signing waivers to say I wouldn’t use the ship’s medical services, as the Mexican clinic had deemed me unfit to travel. Days later, back home in California, I was purple from the waist down. I was in an immobiliser for six weeks, to keep my leg straight, and it was three months before I could drive. While it wasn’t broken, the muscle was balled up. Even now, that leg aches every day.

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I still have flashbacks. I have to sleep with the TV on, as I can’t bear the silence. Sometimes my husband and I wake ourselves up screaming in the night. We didn’t sign any waiver at the ecopark, but we weren’t entitled to compensation. I never got an apology from the company.

How does a zip line give way like that? The company denied that the line had become detached or broken, but the fact that I ended up upside down in a tree means something went very wrong.

You hear about deaths on zip lines. Some people fall from 20ft and die, so to fall from 500ft and walk away without serious injuries is mind-boggling. Zip lines are a gamble, but then life is a gamble. It’s not going to happen to everybody. Do your research, but don’t live your life in fear.

• As told to Sophie Haydock

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