The phrase "became insane" is a strong and potentially harmful way to describe someone's mental state. There are many more appropriate and sensitive ways to express this idea. Here are some synonyms that can be used instead: suffered a mental breakdown, experienced a psychotic episode, lost touch with reality, descended into madness, had a nervous breakdown, suffered a mental collapse, succumbed to a mental illness, experienced a mental health crisis, went off the deep end. It's important to use language that avoids stigmatizing and demonizing individuals who are struggling with mental health issues, and to choose words that accurately capture the nuances of their experiences.