"WW3 comes from him then he defaults to the “I’m no good” ." I assume this him referring to himself, or is he referring to you?
As I read this, I could see the lust situation. But it really only sounds like a symptom of something much deeper. I say that because I have struggled with such things and still have to be vigilant. Every man does really. But, again, it is a surface thing if it is just the "old wandering eye." With the way you describe things playing out between you, it is deeper. There are so many things I think about that I have seen in my own marriage and in friends and family that could be at play. Habits like this form for a reason. There is always a payoff or a relief that they are addressing. Maybe it is valid, maybe it is not. But it is there. I would suggest to you to look behind the behavior and seek to gain some understanding to the reason that the habit is there. And I would say to disregard the obvious: 1. there is an attractive female close by and 2. your husband must want to have sex with her. You will likely be chasing the wrong devil if you only see those.
You have shared with him how it makes you feel already. He responds with anger. I can't count how many times I saw that in my own FOO. And then I have been the one that has used the "I'm no good" defense. That is really an attack and we all know it. But it also reveals something that can be useful information if you think he is at least somewhat sincere in his words. I was somewhat sincere in that I truly did feel like I was broken, I was damaged and had no power to change myself in the ways I was acting (my problem was porn - not that much different). So I lashed out. It's what we do. "Let me make you feel bad so I don't have to feel so bad about myself." Crazy and foolish I know, but, its what we do. And we do not realize how ineffective and counterproductive it is. It drives us farther and farther away from what we really want.
Look, I am not in any way trying to defend your husband's insensitive, selfish, likely very sin oriented actions. They are probably inexcusable, as mine have been. But there is almost always a reason behind them. And unless you can help him get to that reason and address it, you could be doing just as he may be doing - addressing the wrong demon in the wrong way and in fact be empowering the one that has control now. You may be at a point where you have to take drastic measures. All we know is what you write here. Just be careful. Slipthegrasp hit upon it well in that to form a new habit, people need a reason, just like they had a reason to form the old/bad habit. If you just attack the old habit, they will just defend themselves instead. They also need a reason to break the old that makes sense and offers a reward. They have to want to. We all, ALWAYS, only do what we want to do- even if it is the lesser of two evils. We chose the one that is less painful. I don't "want" to go to work, but living on the street would be more painful. I want to look at porn, but doing so costs me more than it pays off. I have changed the reason/reward, and that changed the habit. You can't just look at the action alone....