The most concerning aspect of your letter is your admission that you are “unable to resist rubbing myself against them at every possibility…” That suggests that you are unwilling or unable to stop yourself from engaging in this behavior.
What you are doing is illegal. You could go to prison.
You asked “how can I stop doing this before they realize what I am doing?” The answer is to avoid all situations in which you could act out inappropriately. That means never going to swimming pools since you know they are a problem for you.
You know it is a problem yet you go anyway. Because of this, it is imperative that you seek help. That is the responsible course of action. Get help now or risk being arrested for a sex crime, labeled a sex offender and perhaps spending the rest of your life in prison.
Your behavior may be consistent with frotteuristic disorder which involves recurrent, intense arousing fantasies, urges or behaviors, that involve touching or rubbing against a nonconsenting person. Consult a mental health professional. They will know how to help you. Please take care.
Dr. Kristina Randle