The 26-year-old struck up a conversation with Strictly star AJ Pritchard after being dumped by his sibling.
AJ made the revelation while speaking on talkRADIO.
He said: “She spoke to me. She sent me a message actually afterwards and said she feels like she knows the family and she could only praise Curtis about being honest.”
He added that he would be seeing Amy and the rest of the cast on Sunday on the Aftersun programme.
AJ, a professional ballroom dancer like his brother, admitted Curtis’ treatment of Amy was “brutal”.
Curtis left the nation stunned after telling Amy his “head had been turned” just as she declared her love for him.
The heartbroken former air hostess was so heartbroken she quit the show and returned the UK.
Want to make sure you get the latest updates from the villa? Or just can’t wait 23 hours to find out what happens next?
Sign up using this form to receive daily updates directly to your phone – and we’ll send the big breaking news to you as well.
AJ told talkRADIO: “Sometimes he was maybe a bit too brutally honest. He could have let her down a bit softer rather than saying ‘yes, I don’t see myself marrying you and having kids with you’.
“That was harsh, I’m not lying, it was harsh.”
However, he conceded saying he felt “it’s better to be honest”.
Amy returned to the UK on Wednesday afternoon after sensationally quitting the show following her heartbreaking dumping.
She was seen sobbing heavily as she ran into her mum’s arms in an emotional reunion.
She received 24-hour aftercare and therapy to help her cope with her heartbreak before boarding a British Airways plane home from Spain.
Amy was the fifth Islander to leave the villa within 24 hours.
Love Island continues tonight at 9pm on ITV2.
Do you know any of the Love Island cast? Contact email@example.com to tell your story