It was mentioned that they had run out of medicine so it's in line with her character wanting to help and not be a burden. Why they don't have any magic healers, however...
Regarding the philosophical question of 'is this gay': The author clearly created a character that looks like a girl, acts like a girl, and for all intents is a girl. But he's a guy. Where does this leave us?
We're (most of us anyway I assume) attracted to him because of these aforementioned...