The former Texas Rose was tricked into thinking she was partaking in a promotional project, as her boyfriend put his plan into action.
"A lifetime dream of traveling to Santorini was made that much sweeter with this amazing proposal," Hayley said.
"After receiving a letter from the hotel asking for couples to volunteer to be part of a promotional project including photos and videos "we" agreed to participate."
On the evening in question, her boyfriend Davey took her on a sunset cruise.
"I received an amazing massage and the opportunity to get my nails and hair done through this 'promotional project,'" Haley recalls.
" Thoughts crossed my mind whether or not this might be the night we would get engaged but the photo crew reinforced that this was strictly a promotional project for the hotel."
However, as she looked out over the water, she saw two people holding a banner with the proposal printed on it.
"Looking back toward Davey I saw him on one knee holding up a ring asking me to spend the rest of my life with him."
"It was then I realized the entire thing had been a set up, there was no promotional project, he had planned the entire thing as a way for us to treasure this memory."
Haley said the experience was one of the "best surprises of [my] life."
Watch the moment, below.