Lust usually feels great... and horrifyingly 'emptying'. It is very powerful, especially because it creates bodily sensations, and that kind of thing is incontrovertible. The body is convinced that it is truly good and that we need it. And you cannot argue with a body... it does not speak English, or any language.
I believe that the only way to communicate with it and possibly convince it otherwise, is with pain. And that is what addiction produces. It adds layers and layers of new pain on top of the old pain we thought it would cover.
And I do not believe this pain can be contrived, meaning that we cannot inflict it on ourselves intentionally - it must naturally grow out of the lusting process. Rolling in snow, fasting, and giving ridiculous amounts of money to tzedakah (or even burning it up!) will avail us nothing. The body cannot be fooled.
I believe that a normal person may not get this pain at all, but I think that an addict is guaranteed to get it, eventually. Hopefully the cost by that time will not be too great for him and his health, for his wife and family (if he has them), for his community, and for Klal Yisroel. That is why Guard likes to write about "hitting bottom while still on top". We all hope to do just that, but just look around and you'll see that giving up our drug before carrying it becomes impossible... well, that feels like giving up my life for some worthy cause - as a young man! I have so much life (including nice sex and lust) to look forward too! Let the old, decrepit folks do it, rather than me... I am not kidding. Many of us express the feeling that if we don't have this thing we are lusting after, we feel like we are facing death itself. Otherwise, what is the big draw? "Just say no!"
Nu?
So here is a short list of the side-effects of lust that help identify it (so we can tell the difference between lust and love - even when with our wives):
Lust rarely makes me happy; it always makes me feel uneasy afterward; it never makes both of us happy; it eventually makes one (then both) of us miserable.
Lust does not allow me to give and help people - it makes me give only so that they'll love me and give me something I crave.
Lust allows no place for a real G-d - a G-d who has my best interest in mind (= loves me), because lust forces me to either ignore G-d or constantly grovel back to Him...
In the moment, lusting feels uncannily like it makes perfect sense, while true loving makes me and my life make sense.
Lust makes me count and recount my pretty-weather friends, while true love leads to making friends that count in any weather.