Shannen Doherty is getting candid about her cancer journey.

On Tuesday, the Beverly Hills, 90210 star, 52, opened up about the highs and

lows she experienced after she was diagnosed with breast cancer in 2015 on her new podcast Let’s Be Clear with Shannen

— including how she discovered her own “strength” to keep battling back.

“I really learned a lot about myself,” said Doherty. “And I learned a lot about the people in my life. I learned about my own well of strength and being able to dig deep.”

Doherty went on to describe several instances when she felt she wasn’t able to pick herself up out of bed after particularly rough days with the disease and its treatment.

“When I dropped down to 92 lbs. from chemo and was incredibly dehydrated, I had to still get out of bed,” she recalled. “My husband at the time, sort of begging me to keep going and my mom literally trying to pick me up out of bed and get me to the doctor… at that point in time I thought that I wouldn’t survive it.”

Shannen Doherty at “BH90210″ Press Conference in 2019.
Vera Anderson/WireImage

Doherty added that she ultimately remained resilient thanks to the “kindness” from her family and friends and strangers who “connected with her” and shared their own stories about their own cancer treatments.

“To have that connection… It sort of wrapped me into this cocoon of safety, as cheesy as that may sound, as sappy as that may sound, it really did. It made me feel less ostracized from the world and like I was a part of something, which then started my feeling of deep, deep responsibility to share my story,” said Doherty.

The actress and cancer advocate said that through all of it, she was able to find her true purpose to “number one, help others going through what I was going through and number two, possibly speed up cancer research [and] possibly get more money behind it.”

Shannen Doherty attends the 9th Annual American Humane Hero Dog Awards.
Jon Kopaloff/Getty

Doherty has long been open about her cancer journey. After her initial diagnosis, chemotherapy and surgery, she went into remission in 2017. By 2019, however, the cancer returned — and she announced her diagnosis of metastatic stage 4 cancer the following year.

In June, she shared that the cancer had spread to her brain. At the time, she posted a video on Instagram of her undergoing radiation therapy.

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A few months later, in a November cover story interview with PEOPLE, the Charmed actress revealed that the cancer had spread to her bones, but she was receiving treatment and hoped to get into clinical trials developing new treatments to treat metastatic breast cancer.

“I don’t want to die,” Doherty said at the time. “I’m not done with living. I’m not done with loving. I’m not done with creating. I’m not done with hopefully changing things for the better. I’m just not — I’m not done.”