"C'est ma vie" means "It's my life" in French. This song is a message to all the people that want to tell you how to live your live while completely disregarding how you want to live it or your point of view. Middle fingers up to all them naysayers and doubters. If you want to do this or that, you should do exactly that and there is nothing they or anybody else should tell you about it. Live your life, it’s yours and you only live it once.