Dear tikounberith:

That’s a real problem we all recovering lust addicts are dealing with it, I can relate to it as well. Here is what helped me; an old childhood memory:

True story: Years ago, as a child, we had a neighbor, an old lonely lady who have used to feed cats in her backyard daily, not pets but street cats. Our backyard was always full of visitors, cats of the street who knew someone will welcome them nicely in this place and provide them with free meals.
One day the old lady moved away and a new resident moved in.
No one informed the poor cats the party is over… In the begging the disappointed cats kept coming back day by day to only to be welcomed with spitting and stones by the new neighbors kids. Despite all efforts of our desperate new neighbor who was petrified to see these visitors - to expel the cats with all possible tools, they kept coming back.
However as the days and weeks passed by the stream of the visits decreased from day to day, and that encouraged our neighbor to go on not to let them in the yard, until it came to a point where they totally disappeared.

Same here my dear tikounberith, the bad thoughts and fantasies who were used for a long time to find a warm home in our hearts and brains will soon realized they are not welcome anymore, they will slowly loose interest in us. As the time goes by you will less and less be bothered by them if you only don’t let them in.

1) The fact that you know that this problem will fade with the time - as ‘shalom bayis’ said – this fact make it so easy to deal with triggering images or fantasies.

2) L’meiseh, in my experience, the best way to deal with them when they appear in my mind is by giving it over to hashem.
Whenever I tried to fight with them and “push” it away they always won. But when I declared defeat, I talked to hashed and admitted (I really believed it just from my own statistic…) that I’m powerless over this image or fantasy and if it depends on my power I would for sure get knocked down, and asked hashed to remove it from me, IT ALWAYS worked, they got loose and I could handle it easily.
What a logical paradox, you have to declare defeat in order to win the battle, but matter of fact it worked and still works like magic not only for me, but for many more thousands recovering addict, I can’t explain it.