The actress, 49, said that despite their amicable split, she wanted to stick "handle with care" tape across her forehead to warn people that she was not herself at the moment, reported Harper's Bazaar.
"You go through massive grief - it is a death of a relationship, so it's utterly bewildering. Your identity, everything, changes," Carter said.
"There's a great quote I've stuck next to the kettle. It's from Alice: 'I can't explain myself... Because I'm not myself', Everyone always says you have to be strong and have a stiff upper lip, but it's okay to be fragile," she added.
"I feel very self-sufficient at the moment. I'm just going to work out who I am on my own and it's quite liberating."
She has remained close friend with Burton, 57, with whom she has two children, 12-year-old son Billy and 8-year-old daughter Nell.
"I understand him very well and he understands me. It might be easier to work together without being together any more. He always only cast me with great embarrassment," she said.