Without life

I was hoping to get my Christmas flower bouquet, that was so beautiful, to last a bit longer. I threw out some of the worst looking flowers and tried my best to make the rest look pretty but to no avail. No matter how I fluffed and arranged they still looked bad. Finally I realized no matter how hard I try to make them look pretty they won't, they can't... they are dead. That is my life/works without Christ.
It is my take that, that is what the filthy rag reference is about. The menstrual rags were a result of no life in the blood. So our works without Christ are like filthy rags, proof of no life. The only blood that gives life is Christ. The only works we can do that lead to life are in Christ. Christ is all about life and to the fullest.