'Black Keys' Singer Dan Auerbach -- My Suicidal Ex Is Endangering Our Kid

Black Keys singer Dan Auerbach is in a feud with Jack White ... but it pales in comparison to the all-out divorce war Dan has been having with his estranged wife.

The allegations in Dan's divorce from Stephanie Gonis are shocking. For starters, he claims she tried to commit suicide twice in one day -- the first time by allegedly gashing open her leg and ankles in front of their daughter ... the second time by almost burning their house down.

Stephanie fired back in her own legal docs -- obtained by TMZ -- claiming the leg-gashing "suicide" attempt was the result of years of abuse during the marriage. As for the fire ... she says it was just an accident.

According to docs, Stephanie voluntarily committed herself and spent time in a treatment center.

A judge has given Dan temporary custody of their daughter. Stephanie gets supervised visitation for now. The judge won't give her additional parental rights until he's convinced she's mentally stable and is not putting their daughter at risk.