Friends in this context are more appropriate than family, I find. A friend who quits with you is a lot better than one just being a listening ear for your efforts. Additionally, it may sound horrifying to hear, but it in all probability is true: best method would be to quit cold turkey. Set a date (about three seconds ago) on which from that point in time you won't touch the stuff from now on.
A justification for such line of thought can be concluded quite logically in that you don't need it and you'll be better off without porn:
Sexual gratification, for sake of this example, is measured in bowls. You have let's say five bowls per month that you pour out in the exertion or reception of sexual gratification. In the ideal relationship, all five bowls are spent on your significant other. When you cheat, you look at porn, masturbate etc, you are having part of this amount of sexual gratification spent on those activities instead of your significant other. Instead of your significant other receiving all five bowls, they're only getting one (or two, or any number other than five), because you're satisfying much of your desire for gratification though means that are not that person. In essence of sexual gratification therefore, it is practice of cheating on them. Cheating on them in the same way that you would cheat with a person; with a page of a magazine, or the bits and bytes of a programmed website.
When all of your gratification is spent and maintained on one concentrated source (your other), then the sensation will be all the better because they're the only medium you permit yourself.
The mindset in which wherever sexual gratification is obtained other than your signigicant other, is a method of betrayal (or theft on the part of those exterior materials, to shift the blame) on your significant other. If you don't have one, that makes it much harder, but that's where the friend can certainly help. Rely on each other to keep clean for the sake of each other and the task. Additionally, kill the weeds at the root; stop going to the websites that you frequented in your addictions, block offending material however possible, destroy magazines that you may have. It's a lot easier to control the mind from sexual gratification via fantasies once its been deprived of sources from which to draw inspiration.