Demi Lovato [1] is really happy for her ex Joe Jonas [2]. Shortly after he announced his engagement to Game of Thrones actress [3] Sophie Turner on Instagram, the "Ruin the Friendship [4]" singer sent them a sweet message in the comments. "HUGE CONGRATS," she wrote. "Sooooo happy for the both of you!" Demi and Joe briefly dated in 2010 [5], but have remained good friends since their split. She even opened up about the moment she fell in love with him [6] while they were filming their hit Disney Channel original movie, Camp Rock, during a recent YouTube video for her documentary Simply Complicated [7].