you just need a woman who is porn addicted too. Then you live in paradise. Let the perverts rule the world.
Jokes aside, I agree. Addictions are usually an attempt to self-medicate underlying psychological traumas, be they 'constructive' addictions (workaholic-ism) or destructive (alcohol, drug, gambling, sex, pornography, video games, sports, eating disorders etc). In most cases, I think addictions are a form of escapism.
Exercise will definitely help with the stress. You may not believe it now but try it. And not just once. You won't like the first day. Or the first week. By the time you get exercise into your daily routine you'll feel better both physically and emotionally.