Lady Gaga [1] and fiancé Taylor Kinney have ended their five-year relationship, according to reports [2]. It's still unclear as to who did the breaking, but sources say the couple, who got engaged on Valentine's Day [3] last year, decided to pull the plug in early July. Although Taylor and Gaga hadn't been spotted out together recently, they tended to keep their relationship [4] pretty private, so it didn't raise eyebrows. The "Born This Way" singer is currently on vacation [5] in Cabo San Lucas and has not officially commented on the news. Until that happens, check out all the other celebrity couples who have called it quits this year [6].