What do you think should happen to people who grope other people?
> A friend was asked out on dates, unsolicited, multiple times by coworkers.
What's the alternative? How in your world are people supposed to date?
> In all cases, what can you do to challenge these things without being seen as "the crazy one", "too sensitive", "party pooper", or whatever?
I'm not implying that you are any of those things. Did you ever consider the possibility that maybe you are too sensitive?
If you interact with a diverse group of people, they will do and say things that will offend you, such is life, the only way to avoid it is to ensure that you only interact with likeminded people. Expecting everyone to adhere to your values is tyranny.