That's an old fear from childhood, when you learned that people around you cannot be trusted not to touch you in inappropriate ways. In a way that's a false lesson, like many of the things we learn in abuse, because in reality many people can be trusted. But for the abused boy it's a survival skill. At first he trusted everyone, but look where that got him? So now he trusts no one.
These ideas don't disappear just because we are adults now; they sink beneath the surface and can continue to control and affect us, sometimes without us even noticing that this is what's happening.
People around you are in most cases not perverted at all; they are just walking past you. But when they do that, Little Eric goes on red alert because of what happened to him in the past.
This is a topic to discuss with your T. Once we do some Inner Child work it becomes easier to give up these old strategies, which as adults we no longer need. If the little guy feels safe now, he will be less inclined to freak when things happen that remind him of the past.
But aside from that you can also tell yourself that you are not that defenseless boy anymore and you can take care of yourself. You can also tell yourself that in most cases the other person isn't doing anything suggestive at all, and the feeling you have is a defense and survival strategy you have held onto from boyhood. This might help too.
Nobody living can ever stop me
As I go walking my freedom highway.
Nobody living can make me turn back:
This land was made for you and me. (Woody Guthrie)