'Biggest Loser' Season 8 Finale Surprise Engagement!

After meeting on the Biggest Loser ranch for the eighth consecutive season of the life-changing NBC weight loss show, contestants Antoine Dove and Alexandra White stole the thunder away from 39-year-old winner Danny Cahill with a surprise proposal. Antoine, 23, stunned his now fiancée Alexandra with a gorgeous diamond ring live at the Biggest Loser season finale on Tuesday night. "We went through a lot together," Antoine tells OK!.

After both being eliminated early on in the show, the couple stayed in close touch and claim to have bonded over their journey to a healthier, new body.

"We went through a lot together, a heck of a lot together and as we got closer to the end of the journey, I felt more and more close to Alexandra," Antoine exclusively reveals to OK!.

And even though Antoine has now lost 152 pounds and Alexandra 91 pounds, Antoine tells OK! that he knew his 20-year-old partner was meant to be by his side from the start.

"In my heart I knew that she was the one for me the minute that I laid eyes on her,"Anoine gushed to OK! in L.A.

And while Alexandra assures OK! that they have "grown individually and as a couple," Antoine knows how important having his girlfriend around was to help in his astonishing weight loss.

"Both of us went home so early in the show and realized how important it was to have that companionship and help," Antoine explained to OK! after the live show.

But, Antoine and Alexandra weren't the only happy couple formed on this season of the Biggest Loser.

Antoine dishds to OK! about At Home Prize Winner Rebecca Meyer and second-time contestant and new boyfriend Daniel Wright.

" Just like we came together, it's a bond that you go through so it goes back to that whole accountability partner and they have each other so I wish them the best!"