There are several synonyms for the phrase "insane passion for". Some of the most commonly used alternatives are "intense love for", "wild enthusiasm for", "obsessive infatuation with", "overwhelming fervor for", and "uncontrolled ardor for". Each of these phrases express a strong and unrestrained emotion towards someone or something. Whether it's a person, a hobby, or a career, when someone has an insane passion for something, they are completely consumed by it and willing to do whatever it takes to pursue it. So, whether you use the phrase "insane passion for" or one of its synonyms, the message remains the same - a deep and uncontrollable love for something that invigorates and motivates you.