The America's Got Talent judge was recently hospitalised after reportedly suffering a seizure.
"The despair - feeling hopeless and unable to believe that things can ever change with David's alcoholism over the years - has affected our whole family. We want our lives to be different, but nothing we have done has brought about change," said Bach.
She also asked Hasselhoff's fans and colleagues to reach out to him. "We ask David's fans, supporters and handlers to take swift action to save this wonderful man's life."
Bach added: "I have always been close to my daughters to comfort and support them as well as always being there for David. We will be forever hurt from this cruel disease. I am grateful for our two daughters, who have been incredibly brave, strong and protective souls."