Newsflash! Being thought about isn't the same as being abused. If a pedophile looks at your kid in the park, if a gay person lusts after you in the gym showers, if a fat chick licks her lips while staring you up and down in the check out line at the grocery store, no abuse has taken place.
"I just found out a sex offender lives on my street! What if he looks at my kid?" "I don't want gays in the military. Would you want them in the showers with you?" "Your friend better quit looking at my boyfriend before I kick her ass."
Until you are willing to admit that you have personally assaulted and raped whatever celebrity you currently crush on, you have no leg to stand on in your quest to avoid being masturbated about. You left your house, people saw you, and maybe some of them committed that vision to memory for later use. Don't think about it and if you do think about it, realize that no damage as been done and move on with your life.