(re) new here and need help

(Sorry for the length)

I'm in my mid-50's and have been fapping since I was 12.

I had signed up about a year ago and did nothing with it.

I have had problems in my previous marriages about cheating; but mostly not real affairs, just around the edges, and remote things like phone sex and texting (however sometimes involving intimate feelings). It's clear to me that much of this behavior has been an extension of an addiction to porn and masturbation and an increasingly perverted view of sex (as opposed to normal sex with someone you can touch). I went to 12-step for many years and made much progress on this, but still have been using porn and masturbating consistently (1-4 times a day).

I often have trouble with erections and sometimes go soft when having sex. I adore and am insanely attracted to my girlfriend. She is the only woman I want to have sex with.

I live with my girlfriend and have for over 2 years, and we have had a very rocky relationship to the point where I have been unable to commit long term. I would often want to break up with her, and even tell her I'm doing it, and in these times, I would contact other women and be sexual with them. I have justified this to myself and her that it's because our relationship has such problems. However, the truth of the matter is that it's related to my addiction to distance sex/porn/masturbation as a way to sooth myself.

In the last month, our relationship has finally settled to the point where I want to permanently be with her. We have both made huge changes for the better. And yet, when I was out of town for 2 weeks, I tried to text a former acting out partner. After telling this to my g/f, it broke her heart, and I fear that I will have lost this relationship; she has had enough. I have to wait and see how it goes. I have been open with her about having to work on this problem and being on this site. I might share this post with her.

In the last 5 year or so, I have has fantasies of other men having sex with my wife/girlfriend, I think primarily because I have been unable to deliver in the way I want. I think this is another side effect of the porn.

This sexual deviance all needs to stop if I'm going to have any happiness. I am half way through reading Your Brain on Porn, and it's clear they are talking about me. I see how it all fits together, and see how I really need to go through a reboot process. And that it's probably going to be very tough.

I have been concerned about my relationship with my girlfriend in that she does not want sex as much as me, and yet, at times, I'm unable to perform, or perform well. And I realize that I have put way too much emphasis on sex with her. I think this is yet another part of my imbalance.

The last I had PMO was 2 days ago. I'm just going to keep going.

Thanks for the community here.