Shannen Doherty was in the mood to celebrate on Monday night.
An eyewitness tells ET that the 45-year-old actress -- who revealed her battle with breast cancer earlier this year -- appeared to be in "good spirits" and "laughing" while dining with a friend at Nobu Malibu. "She even said she was 'very happy,'" the eyewitness said. "It looked like she was there celebrating something."
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Doherty shared on Instagram that she was indeed celebrating with her pal, Ann Marie Kortright. "Love girls night with @annemkortright helping me celebrate feeling good enough to eat before Wednesday's chemo. #bff #fightlikeagirl #cancersucks #warrior," she wrote.
Earlier in the day, ET obtained documents confirming that the Beverly Hills, 90210 star had settled her legal battle with her former management firm. Doherty sued Tanner Mainstain, claiming Mainstain allowed her insurance coverage to lapse, which she says kept her from a regular checkup and thus caused her cancer to go undiagnosed. The actress landed a settlement in the $15 million suit, but the amount is undisclosed.
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In an emotional interview with ET last month, Doherty revealed her struggle to stay strong amid her breast cancer battle. "It's hard. I started thinking that I wasn't going to live... I don't look past today," she said through tears. "I want to believe that if I fight, I'm gonna be OK."