"Beware any trolls out there - you're not as anonymous as you think you are... According to our Fed friends....so if you don't have anything nice to say I suggest you shut it - and get back to the pretty pictures on your new profile - (although I do have a record of your not so subtle threats) [sic]," she wrote in the long-winded post.
Adding: "Be kind people. Be real. Be authentic - or seriously - bugger off Instagram.
"Most of us on here" Ain't got no time for haters. Sayonara," she concluded.
As soon as the post went live on her social media, Rebecca's fans were quick to comment.
In fact, more than 4,922 social media users jumped on the actress' Instagram page to like or to leave a comment about her situation.
One follower said: "Cool photo. not sure why people say such unkind things , be kind to one another, love makes the world go around ... not hate. Stay safe [sic]."
Another added: "So sorry that you are experiencing this. You seem like such a kind, warm hearted person. Take care."
The Daily Mail Australia has reached out to Rebecca's representatives for comment.
Meanwhile, the New Zealand born star is back on our TV screens in the new show, Wanted, on Channel Seven.
Speaking of her new show, Rebecca told News.com.au: "It's two women, at a bus stop, poles apart, nothing in common.
"They've been standing at this bus stop every morning at 5am for 18 months, have never spoken a word to each other. Then one morning this incident happens at the bus stop which is going to change their lives irrevocably, and they are forced to look after each other and become friends to survive."
Rebecca also lent her skills to producing duties while on the show.
