I am an addict, and this problem took me for a ride for over 20 years, always getting worse. I learned, studied all about the Yetzer Hara, went to Rebbis, shrinks, and read books, learned harder, and did tons of teshuvah....
Here is what I learned:
I masturbated for years until I went to Eretz Yisroel and stayed clean the entire time while learning b'hasmodah in yeshiva - came back to NY for two months in between and acted out twice (quite an improvement, really), then went back for the second year, again clean the entire time.
My Rebbis in Eretz Yisroel basically gave me the message that if I leave a life of Toraso u'mnaso and went back to the unholy land, I'd be "off the Derech" and out of Hashem's personal Hashgocha; that He would not love me any more and that I was basically a dirtbag.
But I had no choice. I was 20, had no job, had holocaust parents who truly loved me, and was not of the type of strong constitution to "go it alone", anyway. So of course I came back to the U.S.
I felt sure I was a dirtbag; a loser in the eyes of Hashem.
My mentality tortured me and played a major role in my innocent, growing need to get pleasure in lust. After all, it was the only truly reliable way for me to feel anything really enjoyable.
I went to university and to yeshiva in U.S for a while and got married. Kollel, more school, a job, kids.... that's when my problem really took off! By 1995 I was just awful, but living a double life - a generally acceptable father, husband, and person... but not on the inside.
I'm stopping my story here in order to try and get this point across:
The power of dejection - feeling "I am not good at all", is horrifying. That pain drove me deeper into addictive behaviors. Today, I know (and so does my wife!) that I need to daven in a minyan and learn regularly, maintain proper hygiene, stay in touch with Hashem, be honest and have integrity... Not just because they are the right thing to do, but because if I do not, I will act out! There is only so much self-condemnation I can take before I will need to medicate. It's as simple as that.
Surely Hashem understands this and wishes me to take good care of myself, even using His mitzvos. Isn't this "liShmah", in the end?
Nu. Even if the answer would be "No!" (c"v), I'd do it all anyway, just to stay sober. Cuz sobriety is life to me. And I want to live, thank-you.
The annoying flip side of this, however, is learning how to accept occasional mediocrity in learning and davening themselves! If I demand perfection in even those basic areas, I will guarantee failure. This is a hard pill to swallow for many. It seems like a contradiction but: As much as behaving right is part of feeling OK about myself, accepting my humanity (imperfection) is part of it too. Anything else is just plain ga'avah - and deadly. But that is just reality, and growing up. A mature person's Avodas Hashem really is just progress, not perfection. It really is ratzoh vashov. I really am human.
When it comes to my essential acting out behavior - using masturbation and porn - I can't tolerate it at all, true. But that is a gift from Hashem, too. We do whatever it takes to avoid that stuff, for it sets us on a road of insanity.