The 31-year-old, who is mum to eight-month-old Bowie and 11-year-old Rylee, said she had been up with her son since 3am and he just wouldn’t go to sleep.
And although Holliday said the majority of the time she is able to “put some lipstick on and deal with it”, this day things just got too much to bear.
“Most days I drink my coffee and smile at every little thing he does thinking it’s the best thing in the world, but not today,” she wrote on Instagram on 26 February.
“I’ve been crying for nearly two hours and I’m crying as I write this.”
Holliday continued: “I’ve reached my limit, exceeded it to be honest.
“My confidence has taken a blow with this birth and it wasn’t until this morning I realised why: The pressure of ‘looking good’ for a living is too much today.
“When your face is breaking out from the hormones of breastfeeding and total exhaustion from lack of sleep, bags under your eyes, patchy red skin and to top it off no energy to work out or leave my bed... how do you do it?
“Is any career understanding when you show up at negative 10% because your kids wouldn’t let you sleep and you want to hide under your covers and cry?
“Not many. I hope one day that changes and society views mothers as the flawed human beings we are that are just trying to keep our shit together like everyone else.”
Holliday shared the honest message alongside a selfie of herself crying. She was showered with words of encouragement from other mums who have had similar experiences of motherhood.
“It gets tough, it does,” one mum wrote. “I remember many-a-time crying. You’re a queen and there’s lots of us trying our best. It’s all you can do.”
Another mum wrote: “You are a beautiful, brave and awesome lady. Cry your heart out, it’s fine. We all been through this.”