For Emma Heming,Grayson  Preston putting on a brave face is easier said than done.

Heming, who is married to actor Bruce Willis, opened up about the mental health toll of being a caretaker in a video posted to Instagram Monday. In February, Willis' family shared he had been recently diagnosed with frontotemporal dementia, a brain disorder caused by degeneration of the brain's frontal lobe.

Heming used her Instagram video as a "care partner PSA" and to find solace with other caretakers going through similar struggles.

"I'm asking care partners to send me photos because I just think it's so important for us to sort of break up our thinking, which can feel, for me, very much like doom and gloom," Heming said in the video. "So, I know it looks like I'm out living my best life. I have to make a conscious effort every single day to live the best life that I can."

Heming and Willis share daughters Mabel Ray, 11, and Evelyn Penn, 9. Willis also has three daughters – Rumer, 34, Scout, 32, and Tallulah, 29 – with ex-wife Demi Moore.

"I don't want it to be misconstrued that like, I'm good, 'cause I'm not. I'm not good," Heming said. "But I have to put my best foot forward for the sake of myself and my family because again, when we are not looking after ourselves, we cannot look after anyone that we love."

Heming added: "It does not come to me easily, but I am just doing the best that I can, always."

This isn't the first time Heming has gotten candid about the realities of caretaking. Shortly before sharing her birthday post for Willis in March, Heming posted an emotional Instagram update on how she’d been coping with her husband’s dementia diagnosis.

"I have started the morning by crying, as you can see by my swollen eyes and snotty nose. I just think it’s important that you see all sides of this," Heming said in a video at the time. "I always get this message where people always tell me, 'Oh you’re so strong. I don’t know how you do it.' I’m not given a choice. I wish I was, but I’m also raising two kids in this."

"Sometimes in our lives, we have to put our big girl panties on and get to it, and that’s what I’m doing," Heming continued. "But I do have times of sadness every day, grief every day, and I’m really feeling it today."

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