I think her "rule" is unrealistic. You'll be looking at other women in public all the time. Some will be showing cleavage.

If you're on a diet, you'll be looking at ice cream and cookies in stores, in movies, and from people around you.

Glancing at something isn't the same as touching it.

You're on the internet in 2023. I don't care who you are, a half-naked woman is bound to pop up from time to time.

OP, he may also feel the same way: awkward and regretful. Talk to him and figure it out.

This is one of the craziest TIFU stories I've read. Damn, OP, sorry. But what a hell of a story.