41 Days Stranded at Sea: The Harrowing, Heartbreaking Real-Life Story Behind New Movie 'Adrift'

Spoiler Alert! This story contains major spoilers about the plot of the new movie Adrift.

The summer of 1983 started out like a fairytale adventure for 23-year-old globetrotter Tami Oldham Ashcraft.

The California native got engaged to her British boyfriend, Richard Sharp, and several months later the two experienced sailors set out on a dream trip from Tahiti to San Diego on a luxurious 44-foot sailboat. Less than two weeks into their trek, the pair — played by Shailene Woodley and Sam Claflin in the new movie Adrift — were trapped in a devastatingly strong hurricane that changed their lives forever.

Ashcraft, who originally detailed her ordeal in a 1998 self-published memoir Red Sky in Mourning, says that although she and Sharp received radio warnings about the developing storm, which started out as a tropical depression and quickly gained in intensity and speed, they were unable to outrun it.

“We ran from it for three days trying to figure it out, because it kept changing direction,” Ashcraft recalls to PEOPLE. “The storms are going twice your speed. We couldn’t make that kind of time with the boat to get out of the way.”

When the hurricane fully descended upon them on Oct. 12, Sharp had sent Ashcraft below deck to rest. The last thing she remembers before the boat capsized and she was knocked unconscious is her fiancé screaming.

“When I woke up from being knocked out for 27 hours, I didn’t know where I was,” she recalls. “I was like, ‘Where am I?’ The boat’s half-full of water at that point, I couldn’t even really remember anything. Then I started moving and unlatching myself [from her safety suit and various debris], looking around going, ‘Oh my God. Richard. Where’s Richard?'”

All she could find of Sharp in the midst of the wreckage was his broken safety tether hanging lifelessly over the boat. While the reality of her grave situation swept over her, so did the awareness that she was badly injured — her head was split open behind her hairline and she had a serious gash on her leg — and drifting aimlessly somewhere in the middle of the Pacific Ocean.

“They were both bad. My head injury I could keep clean somewhat, keep bandages on it,” says Ashcraft. “Thank goodness it’s underneath my hairline so you can’t see it. It splayed my head wide open, and I just bled. My leg I kept hitting on everything, and then there was so much water in the boat. It would just stay wet all the time. I was super worried about my leg. Then I started ripping up t-shirts and stuff when I ran out of bandages.”

After she self-administered first aid, Ashcraft’s next key survival move was crafting a makeshift sail from some of the debris on the boat and setting course for Hawaii — 1,500 miles away — which she was able to do via her navigation skills.

“What saved my life was knowing celestial navigation, that I could navigate by the sun and get myself somewhere,” Ashcraft says. “You have to do three sights a day, and sometimes I would have to do four. Doing all the mathematics required for that really helped me to focus.”

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It also helped keep her mind off her grief over losing her fiancé in such a tragic way.

“I had to tell myself onboard that I couldn’t cry anymore, because I was losing way too much water,” Ashcraft says. “My water supply was very limited. I just had a big talk with myself. That inner strength to survive is so strong. You just don’t realize it, until you’re put in a really crucial time that you have to survive. It’s amazing what you can do. That just comes from within really. Then keeping your mind active.”

Ashcraft survived 41 days adrift in the Pacific, subsisting on peanut butter and willpower, before she approached Hilo, Hawaii and was picked up by a Japanese research vessel after sending up a flare around 4 o’clock in the morning.

The ship’s crew members “were shocked,” she recalls. “I was exhausted. I was way underweight — I’m 5’8″-5’9″ and I weighed about 100 lbs. I didn’t even go to the hospital. Can you believe that? I can’t believe nobody sent me to the hospital.”

When Ashcraft returned home to San Diego, the weight of her near-death experience and the loss of her first love fully set in, and she face a long recovery from her injuries, physically and mentally.

“I had the head injury and I couldn’t even read a book for nearly five years. I couldn’t finish sentences, my short term memory was really bad,” she says. “Seeing couples together, that sort of thing, was hard. I had nightmares. I was consumed for years and years with thinking about it. I then realized after five or six years that I could choose when to start thinking about him and the experience. I started realizing, ‘Oh, I’m not consumed by this all day now.'”

Although Ashcraft says her physical injuries healed well enough that she never went to a hospital for medical attention, she regrets not seeking out help from a therapist or counselor.

“I wish I had gotten some professional mental help. I think I could have sped up my recovery a little bit more,” she says. “Not so much the grieving but the mental recovery of reading and that kind of thing. They can give you projects to work on and things, and also just make sure that you’re going around the right track.”

Ashcraft says it took her a full five years before she was able to come out of her mental fog and feel joy again. She returned to the water almost immediately — only these days she prefers power boating to sailing when she navigates near Washington’s San Juan Islands, where she lives with her family, husband Ed, a contractor, and her two daughters.

“We’ve been a boating family,” she says. “I think it teaches the children so much more about life.”

Ashcraft still speaks publicly about her incredible survival story to groups like the Navy Survival School. “I’m glad to help, although I’m sorry I was in that situation. Now I choose when I want to think about it. For many years I was consumed by it and a lot of that had to do with just moving on in life,” she says. “It’s still in your heart. It’s just in a different way.”

Adrift is now playing in theaters.