Behind all addiction is the neuromodulator called dopamine, which is people often think of it as like the pleasure hormone. All addictions have dopamine behind them and they can be behavioral and some of the behavioral ones are really nasty. Pornography just messes with your brain. It turns your brain into a dopamine pump. And ordinary life doesn't give you anything good anymore. The only thing that does is sort of fantasy life and you can get extremely addicted to it. You might as well just be at AA because it turns out to be the same kind of monkey on your back.