Charlotte Gainsbourg says she feels "anxious" about marriage.
The Nymphomaniac star's actor-and-director partner Yvan Attal proposed in 2013 and the couple have children Ben, Alice and Joe together.
Despite the question having been popped, the pair are now unsure if they're making the right decision by getting married.
"I obviously said yes. It was very funny the way he proposed (while he was being honoured at the Ministry of Culture, in front of a crowd of journalists), but I'm not sure we're actually going to do it," she admitted to the latest edition of British magazine Marie Claire.
"We've started feeling a little anxious about the whole thing since. We'll see. After he did that and I said yes, we figured we were quite happy the way we were."
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The 42-year-old admits she and Attal are often "exhausted" and that it can take a toll on their relationship.
She was open about her shortcomings and admitted she needs her fiance to keep the family dynamic stable.
"I'm very unstable; I can be easily swayed," she candidly revealed.
"I don't think I'm reassuring and that's not good for children. I can't help thinking that I've failed something, as a mother. I show them a very vacillating image. Yvan completes me very well in this respect - he is stronger than I am. At least my children have that protection."
With her busy schedule, it's difficult for Gainsbourg to spend quality time with her children.
However, she does take them to work with her when she can.
"As long as my two older children were little, I could take them everywhere, but you can't keep doing that," she said.
"I have taken the youngest with me on the set of Nymphomaniac. It was quite funny, actually, the contrast between these epic workdays and then the nights with this baby girl I was still breastfeeding."
