There's a lot on this sub about the evils of porn, but I feel that there is another way that people fall victim to their urges. There is few ways to completely nuke your life quicker than cheating on a girlfriend/wife.
If the love is gone from the relationship, break up and move on. You'll be safe in the knowledge that you've done the right thing, and you'll save everyone a lot of heart ache.
If you cheat you'll hate yourself. You'll know that you're a person that cannot be trusted.
If you cheat you'll damage another person's self esteem so badly that they may never fully recover.
If you cheat everyone you know will respect you less. They will know you're weak, callous, and untrustworthy.
I've come shamefully close to cheating myself on occasion, when the opportunity presented itself, but thankfully I've always resisted temptation.
If a beautiful woman shows interest in you, let it boost your confidence and move on. Go home to your loving wife and be a good husband. If you're drunk, or otherwise not at your best, remove yourself from the situation as quickly as possible.
Being tempted doesn't make you a bad person, but going through with it will eat away at you. The porn industry has many people convinced that it is natural to allow themselves to be blown about by the whims of their libido, but it's not, be better than that.
I've seen too many otherwise good men completely ruin their lives for the sake of a pretty face as a few hours of pleasure. A huge portion of divorces are instigated because of adultery, and we all know how men get fucked in divorce proceedings.
Don't cheat Kings, you know you're better than that.