When you're in a relationship, do you know everything about your partner? Can you tell if the other person is lying to you? When Lance Armstrong talked with Oprah about his use of performance-enhancing drugs, he never made any mention of Sheryl Crow, his ex-fiance. Did she know anything about it?
However, according to Celebuzz,

the Grammy winner was named twice in the affidavits submitted to the United States Anti-Doping Association, which blew the whistle on Armstrong's use of performance-enhancing drug use.

The affidavit reportedly states that Armstrong called his former U.S Postal Service teammate Frankie Andreu to his hotel room to persuade him to convince his wife Betsy to sign a statement retracting her claim that Armstrong told doctors treating him for cancer than he had taken steroids and Sheryl was reportedly in the room.

Sheryl Crow and Lance Armstrong began dating in 2003. They were engaged in 2005 but split in 2006.