Christina Applegate shared a heartbreaking conversation she recently had with her teenage daughter, Sadie, about her MS diagnosis.

“We got into a big thing the other day — and sorry Sadie, but it has to be said — she said, ‘I miss who you were before you got sick,’” the actress recalled on Kelly Ripa’s “Let’s Talk Off Camera” podcast Tuesday.

“That is just like a knife to the heart because I miss who I was before I got sick too, very much so, every day of my life. It’s such a loss,” Applegate added.

Despite their tense conversation, the “Dead to Me” star said that she “gets up every morning” for her 14-year-old daughter while battling the chronic disease.

“She’s the reason I’m still here and trying,” Applegate, 53, candidly admitted.

The “Sweetest Thing” star revealed her MS diagnosis in August 2021 in an emotional statement on X (formerly Twitter).

“Hi friends. A few months ago I was diagnosed with MS. It’s been a strange journey. But I have been so supported by people that I know who also have this condition,” she wrote at the time.

“It’s been a tough road. But as we all know, the road keeps going. Unless some a–hole blocks it,” she continued.

“As one of my friends that has MS said, ‘We wake up and take the indicated action.’ And that’s what I do. So now I ask for privacy. As I go through this thing. Thank you xo.”

Since announcing her diagnosis, the “Anchorman” actress has been very open about her health journey, revealing in March 2024 that she wears diapers due to the condition.

“Well, you pee … in your pants,” Applegate told People at the time. “Because you probably can’t get to the bathroom in time. So yeah, diapers.”

The “Married… With Children” alum’s daughter shared her own health struggles in June 2024 when she revealed she has POTS — formally known as postural orthostatic tachycardia syndrome.

“I have no clue what it actually is, but it’s something to do with the autonomic nervous system and it affects my heart,” Sadie said on Applegate’s “MeSsy” podcast. “When I stand up, I get really, really dizzy and my legs get really weak and I feel like I’m going to pass out.”

“I hate it for you, my darling. I really hate it for you,” Applegate said in response. “I’m sad. But I love you and I know you’re going to be OK. And I’m here for you and I believe you. And thank you for bringing this to light and awareness.”

Applegate shares Sadie with her husband, musician Martyn LeNoble, who has stuck by her side through her MS diagnosis and breast cancer battle.

The actress was previously married to actor Johnathon Schaech from 2001 to 2007. Schaech applauded his ex-wife in January 2024 after her surprise appearance at the Emmys.

“She danced opening night on broadway on a broken foot! Beat cancer! She’s the toughest human being I’ve ever met! F–k MS! So proud of her! Go Christina!” the actor posted via X at the time.

Schaech also posted a photo of Applegate on his Instagram Stories from the special night, adding in the caption, “We are so proud of you, Christina.”