Jennie Garth says she's found herself in a 'really cool space' at 50: 'I didn’t think it would feel this good'

The Unwind is Yahoo Life’s well-being series in which experts, influencers and celebrities share their approaches to wellness and mental health, from self-care rituals to setting healthy boundaries to the mantras that keep them afloat.

When it comes to staying happy and healthy, Jennie Garth believes it's all about the company you keep.

"I'm just really, really selective about who I spend time with and the conversations we have," the Beverly Hills, 90210 alum, 50, told Yahoo Life. "My circle has gotten quite small by choice. I really have a limited capacity and energy to put out there, and I want to make sure I'm putting that energy into the right places, the right people."

The actress was just 18 years old when she skyrocketed to fame as the beautiful Kelly Taylor on 90210. But as her profile increased during the show's decade-long run, the Illinois native realized she needed to put extra work into her mental health when the cameras were off.

"I’ve been in therapy since I was in my early 20s," says Garth. "I've learned so much about myself and how to take care of myself. When you do have mental issues, whatever they are, you really do feel like you're alone. You feel like nobody else thinks the way you think, or has the struggles you have. But we all have the same struggles. Through therapy, I've learned how to take care of myself."

To preserve her mental health these days, Garth practices meditation for at least 10 minutes a day. She thrives in nature, crediting daily walks with her well-being. She's also an avid golfer, which she calls "a mental game." But one aspect of her mental health that Garth says she'll always be working on is letting go of worry. As a mother — the actress shares Luca, 25, Lola, 19, and Fiona, 15, with ex-husband Peter Facinelli — she's learning to deal with change now that her two oldest daughters have left home.

"I have two full-grown girls out of the house; they live in New York City. There's so much to worry about. 'Will they be happy? Will they be safe? When will I see them again?' It's a constant thing as a mom you worry about as a mom when your kids are out of the nest," explained Garth.

In order to be the best mother she can be, Garth realized she needed to take better care of herself, too. That means limiting the amount of time she spends on social media, even when it's a necessary part of her career.

"You just get tired of seeing everybody’s perfect life, and it's exhausting mentally. It sucks your energy level and, in turn, is bad for you physically," says Garth, who actively tells herself to "stop it — just stop" when she's about to scroll through social media.

But caring for herself also means dealing with physical health problems. About five years ago, Garth realized she was having trouble getting up and down as easily as she used to.

"There was an aching feeling that permeated my joints, my knees my hips," she recalls. "I thought, 'what the heck is going on?'"

Upon consulting her doctor, Garth was diagnosed with osteoarthritis, a degenerative joint disease. Shocked that she could have the condition in her 40s, she soon learned about the stigma surrounding arthritis and aging.

"Everyone associates it with being older, but you can have arthritis at any age. It can affect anyone," says Garth, who blames both genetics and "years and wear and tear" from decades of dancing (she competed on Dancing With the Stars in 2007) and riding horses.

Garth recently teamed up with Voltaren Arthritis Pain Gel to launch their CareWalks campaign, created to empower caregivers with joint pain to care for themselves. It's a meaningful mission for Garth, who not only lives with arthritis but helped serve as a caregiver for her father before his death.

"So often, people focus on the patient, rather than the caregiver," says Garth. "This is an opportunity to flip the script and talk to the people behind the scenes. They’re so often suffering with their own struggles."

When it comes to aging, Garth hit a significant milestone herself back in April when she turned 50. Initially, she felt like it was "a bit of a mental roller coaster," but says she was determined to stay positive in the face of change.

"It’s a milestone. But I have to say, that you do come into a really cool space at 50 — a place of inner confidence and quiet, and it really feels good," explained Garth. "I didn’t think it would feel this good, but it really does."

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