i think it should be alright. i have pet rats as well as snakes. when i first got my snake i hated feeding him becuase i always felt so bad for the rat, then i always asked myself, "who do you love more, the rat or the snake?" the answer was always the snake (esp. because the rats were already dead. lol), so im fine, just explain how you feel to her that way, and it should be alright.
best of luck to you and this chica.