Lyric discussion by sarabuckingham 

Cover art for Trouble lyrics by Lindsey Buckingham

I'd venture to guess this was about Carol Ann Harris. Give Storms a read. It's a great memoir. Carol Ann was Lindsey's girlfriend during the tusk era.

He wrote this song when he was with Harris. Read the lyrics; the song is definitely about a relationship from his past, veeeerrry likely Stevie Nicks.