Welcome d'maot. As someone new to this myself, I am not sure whether its chutzpadik for me to put in my 2 cents, so apologies to everyone.
It seems to me that the most important thing is, as the Holy Yid said, is to try and understand what went wrong.
If I may be so bold as to share some of my story, as an illustration.
I started this when I was young. I wasn't frum at the time and indeed porn and mb were, if not actually encouraged, a normal part of life and certainly to be expected. I expect that in the course of time it will come out that my addiction started then, since I used to, ahem indulge a lot. It stopped when I became frum, and when I got married things were good. Over time we had our problems. Financial difficulties, infertility, clinical depression (my wife's), changing jobs, moving home.
I am coming to believe that when things got too much for me, when I became overwhelmed, stressed beyond my ability to cope, I responded by reverting to my old activities.
Anyway, to cut a long story short. I find that coming to this understanding gives me a way of understanding and therefore controlling my emotions and consequently my actions. The other thing is - if you can see danger up ahead, it is a darn sight easier to avoid. It also helps to identify triggers (those things, words situations which can lead you into harm's way) again, this should help to avoid them.
Ultimately, you can be assured that you are not alone and that we are here to help. You only have to want it.
HW