We often hear wives ask their addict husbands, "how will I ever trust you again?" and the answer is really that the trust may never come, but if it does, it will be her own choice and not because her husband convinced her to trust him. He knows that game of sympathy and proving his 'good-ness' is over. It was all quiet manipulation.
Now the choice of trust will not come from her 'getting the feel' that he is finally a kadosh; nor from seeing that he has become less demanding in the bedroom, nor because he finally really seems to be so careful in avoiding triggers. No way. All that will always fail as a barometer. I know in my heart that I am not ever to be trusted with my own attractions - I am ever more sensitive to lust, not less. This is not guilt nor a madreiga, nor a screwed up shittah: it's just what I experience. Thinking that I am 'stronger' is the single mistake that I have seen guys make that ruins everything - usually leading to greater pain than ever. Because they are not stronger, and they need not aspire to be.
Rather, the trust comes (if she chooses to trust him) from seeing her husband being a reliable father, husband, and worker. He's generally where he says he'll be when he says he'll be there, tells the truth about everything even though it neither makes him look like a tzaddik nor a rasha, and is generally healthy in every department of life other than his addiction. That's the only way.
Having all sorts of fences against lust will never prove a thing at all to anyone - even to the addict himself/herself - because the adage "ein apotropos l'arayos" is talking about normal people! For an addict it's just a silly understatement, and to me it seems the reason is this: For me, an addict, it's not about arayos. At least, not once we are addicted... It's about our survival. When lust enters, I think the addict acts out because of the survival instinct, nothing less. He or she is just doing what their whole heart and mind deems absolutely necessary to survive. And survival trumps everything, and should! Many normals would not think twice about betraying our spouses or neglecting our kids to save our very lives right now. It's not a simple moral choice and shouldn't be looked at that way, in my opinion. That's why most normal thinking is useless to me in addiction (and perhaps even more useless for perverts very early-on in their recovery). And that's why healthy thinking, heartfelt advice, encouragement, mussar and ruchniyus will not work for most addicts I know, in the end. They will fall - to survival. Who wouldn't? Telling them that lust won't help them survive is just plain gibberrish, and in their guts they "know" that! (Ever try arguing with a gut?)
That's how I see it. That's why generally only addicts can help addicts. It's not about sympathy, but about empathy. And with it comes a more realistic view of the absence of trust when it comes to the addiction itself (i.e. not trusting ourselves with lust).
I do not fear to go into a subway, but I'd rather not go. A recovering aklie should probably not fear going into a bar, either. It's never about deciding whether I can trust myself in there yet, but about surrendering and letting G-d take care of me now, wherever I am. If I go into a dangerous situation because I want to, that proves I am not surrendering, period! It's all over, whether I act out now or not. The self-serving will get me in the end, guaranteed, and I'll act out soon.
If you're in a difficult situation, it's Hashem who put you there. It's not your doing. So just let go and let Him care for you.