I have an issue with fantasizing

I sometimes cant stop fantasizing, sometimes ill see something on tv or i might read a book and a sexual position is mentioned that ive never heard of before and i cant stop my curiosity. Admittedly i havent got a lot to do at the moment, i have no work due to a 6 week shut down.
Im so eager to never fap or watch porn again but its such a struggle sometimes.

I drink 3 cups of green tea everyday, i cold shower every day, i read dci banks murder mysteries everyday, i do weightlifting every other day and on the days in between i do either cardio ori walk a couple of miles. I also associate with numerous other people in work and we talk a lot. I dont eat much junk food, i eat quite healthy, i rarely consume caffeine apart from green tea, i have recently started climbing mountains.

Im making such good progress in many ways but i dont want to fall back into my old ways. It really is dragging me down at times and i dont know how to improve this situation. Ive lost count of how many days im on. How can i avoid falling back into this old pattern? Thanks in advance