I'm thinking of platonically kissing a girl who has depressive episodes and going through the first stages of a break up
Could you tell me why you want to put her through something like that?
It's always nice to help someone out and I enjoy making people happy.
You shouldn't take advantage of others. You shouldn't kiss someone who you don't like, either, and use their depression just to make you happy.
But I like her and I think she will feed me cookies after.
She's going through something horrible right now, and you trying to make a move will only hurt her further. Are you trying to bring more pain to your friend? You should be trying to take care of her in non-sexual ways and maybe in a few weeks there will be a spark and you can take it to the level that you'd like to.