Jennifer Garner admits she can’t always live up to the impossible “nice” label she’s been given.

Jennifer Garner arrives at the Apple TV+ "The Last Thing He Told Me" Premiere at Regency Bruin Theatre on April 13, 2023 in Los Angeles, California.

The Last Thing He Told Me actress, 51, said in an interview with Allure published Tuesday that being publicly perceived as “so nice” makes it difficult to set boundaries.

“The problem with, ‘Oh, she’s so nice’ is that when I have any kind of boundary, people think of it as much more than it actually is,” she said. “The problem is being recognized on a day where I’m not so nice or when I have blackness in my soul.”

Garner added, “I’ve definitely had days where I just can’t do it. I scowl at people before they can walk up to me. I’m not perfect, and I don’t think I’m rude, but I’m not good at being fake. I’m an open book of a person.”

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Jennifer Garner Talks Struggling with Her 'Nice' Persona on Bad Days: 'I'm Not Good at Being Fake'

Jennifer Garner. TOM SCHIRMACHER/ALLURE

Elsewhere in the interview, the 13 Going on 30 star opened up about being a mother to her three children — Violet, 17, Seraphina, 14, and Samuel, 11 — who she shares with her ex-husband Ben Affleck, and how being a parent is something she felt destined to be.

“Being a mother was one thing I knew I was going to be,” she said. “I really could have been a mother in any way. I could have adopted, I could have fostered, but there was no doubt I was going to be a mom. I mean, I was the kid with the doll everywhere I went. And I had a babysitting company with my friend Carrie — C&J’s Babysitting — from like seventh or eighth grade.”

Jennifer Garner Talks Struggling with Her 'Nice' Persona on Bad Days: 'I'm Not Good at Being Fake'

Jennifer Garner. TOM SCHIRMACHER/ALLURE

In October, Garner also told Town & Country about dealing with the “nice” label.

“I have no reason not to be nice. My life is lovely. I’m not always just nice. I can also be salty, and I can be taciturn, or I can be really serious about what I want to get done,” she said.

“It’s not that I feel I’m underestimated in that way — I’m not afraid to stand up for myself and say, ‘Just so you know, this isn’t going to fly with me.’ When that happens, I don’t want you to be shocked that I’m a real person.”