I know a pathetic fallacy is when the weather represents someone's emotions, but what is the opposite of that?
Chremamorphism and Zoomorphism
Firstly, pathetic fallacy is not limited to the weather only, it broadly covers animals and inanimate objects. The definition of pathetic fallacy is the attribution of human feelings, responses, reactions and ideas to inanimate objects or animals. Based on this, the opposite of pathetic fallacy would be to give the attributes of animals or inanimate objects to humans.
Objectification obviously means to reduce a person to the level of an object, so it kind of is the opposite of pathetic fallacy. However, with a bit of research I found a term, Chremamorphism, which literally is defined as giving the attributes of an inanimate object to a person. For example,
"Her eyes shone like the stars in the sky,
her face lit up from within, as if the moon"
This passage gives the attributes of stars and the moon to a woman's eyes and face.
Zoomorphism is the attribution of animal qualities to humans, for example:
"He's gone completely batty!"
Referring to a male character as crazy via an animal.
As you can see, I didn't manage to find a single word combining both definitions. However, these should probably be helpful enough.
I hope I helped!