Manon Monastesse says she felt her heart sink when she heard the news: a young woman was stabbed to death and police had arrested her ex-boyfriend. Monastesse didn’t know Daphné Boudreault, but upon learning that the 18-year-old may have been a casualty of domestic violence, she was overcome with a sense of loss. “It breaks you, you see it as a failure,” said Monastesse, who has spent her 25-year career helping women escape spousal abuse. “There’s no equivocating, there’s no rationalizing it, one dead woman is one too many. … You can’t see it any other way than this: we failed this person.