When someone says that "You're a bunch of pussies", it has no connection to any female body part or kittens. It's the short form of "pusillanimous".

pusillanimous

/pyoo͞″sə-lăn′ə-məs/

Lacking strength and firmness of mind; wanting in courage and fortitude; being of weak courage; faint-hearted; mean-spirited; cowardly.

So stop being one.