Here is what I learned today in therapy. I shouldn't view the urge to masturbate as something evil. It's a totally natural urge, which comes from a section in my brain that seeks to have pleasure at all times. I should not feel guilty if I have lust, rather I should reframe lust into 'positive self talk'.
So tomorrow, I need to work on my self talk. I needn't say "oh, I see an attractive person and now I'm going to grapple with this evil urge called taivas nashim". Rather, I'll say to myself, "I'm glad that I am healthy and that Hashem implanted a natural urge inside me. Now I have a job to do. I am to take this urge and be happy about it."
I should tell myself positive things such as: "This natural desire can lead to a certain behavior. I am going to be the one to choose what behavior that is, based on what I know is the right thing to do." I have accepted this desire and I ask Hashem to help me make the right choice.
But I need not put the pressure on me. It's not about "me" controlling the taiva, because the yeitzer harah is a lot stronger. Rather, it's about letting go and saying, "Hashem will take care of me". All I am in charge of is how much I want to stay clean, and to show Hashem that I want His help. I need only work on my "Ratzon" and put it in the right direction, and the results will follow in a positive way.