They also happened to be married to other members of the band at the time.
Christine was married to John McVie, but no after about 1977. Stevie Nicks has never been married.
She was banging Mick Fleetwood too.
And she was banging Tom Petty's producer Jimmy Iovine when he convinced him to hand over 'Stop Draggin My Heart Around' to her as a duet on her album and didn't tell him about the relationship.
He was quite ticked about it.