‘Sometimes I find it hard to show the sad bits of me,’ she wrote.
The 27-year-old went on to say that growing up in a large family of seven siblings and two ‘very strong parents’ made me ‘really tough.’
She added: ‘They hammered it into me to not let people bring me down or hurt my heart.
‘It made me put such a wall up to protect myself especially in this industry. We all have days where people make you feel bad and it’s okay to be hurt by it.
‘I just thought I would write something because I never show this side of me here. I wanted to show this side of me.’
Nicola ended the emotional caption with a thank you to her followers for ‘all of your support’, saying she appreciated ‘kind’ comments.
‘I want you to know I see you, I hear you, and it means a lot to me,’ she added.
The heartfelt words were published alongside a picture of the heiress in bed with her hands on her head looking sad, and another snap of a close-up of her fringe and bloodshot eyes.
In a heartwarming exchange, Selma, 50, was quick to respond to the post, revealing she had met the Transformers actress and was ‘transfixed’ by her ‘kindness’ and ‘grace’.
The Legally Blonde star penned: ‘I was weak and tired and older than your crowd, and you listened. Forever, I will consider you an angel child. In whatever mood or feeling you are under or in. Sending an embrace.’
Nicola was clearly overwhelmed by the Mean Baby author’s response, stating that she ‘can’t even put into words how much your kind message means to me.’
‘Thank you so much you’re so special I’m so lucky to know you,’ she added.
Other famous faces to comment include her husband Brooklyn, 23, who said: ‘You have the most amazing heart xx I love you so so much xx.’
Paris Hilton also wrote: ‘Love you.’
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