Maybe teens and cats aren't actually so tough. We just haven't figured out how to bargain with things they want. IMO, you *can* always find something they want... but you have to stick to the "price" you set for that thing. Then with teens/cats it becomes merely, "How much time do you have?" You have to "detach with love" and be sure to let the price become their problem, not yours.
No need to be worn down by a cat.