Allemand, a 29-year-old model and actress, was brain dead and taken off life support Wednesday after she hanged herself Monday in her home, TMZ reported.
"I am in complete shock and devastated to hear the news about Gia," Pavelka told People.com Wednesday. "She was one of the sweetest people I have ever known. And a very dear friend. My heart goes out to her family during this very difficult time. We have lost an angel today."
The pair courted on Season 14 of "The Bachelor" in 2010. Allemand was eliminated from the competition and Pavelka ultimately proposed to Vienna Girardi, however, they split up several months later.