Billy Joel has opened up about a past suicide attempt that left him in a coma for days, explaining why he made another attempt to take his own life after regaining consciousness.

Joel revisits the incident in his new documentary Billy Joel: And So It Goes , which made its debut at New York's Tribeca Film Festival earlier this week.

The future "Piano Man" solo star was in a heavy-metal style duo named Attila at the time, along with drummer Jon Small. The band released their sole, self-titled debut album in July of 1970. While living together with Small, his wife Elizabeth Weber and the couple's son, Joel fell in love with and began an affair with Weber.

Read More: When Billy Joel Went Heavy Metal With Attila

"Bill and I spent a lot of time together," Weber explains in the document

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