Nathan doesn't attend the funeral, at least not to anyone's knowledge. He watches it from afar. Knowing that Stevie had information he'd rather not fall into the hands of snakemen, or God forbid someone she knows (getting them involved in things he wouldn't wish on anyone), he searches her place for any materials or research regarding the strange things they've encountered together.
@Jonathan-Meadows Let me know if this is an appropriate step. Nathan knows Stevie lived alone.