There was magic spilling through Aphrodite's apartment and it certainly wasn't hers. It made her uncomfortable and, more than that, furious that a Titan could help Rhode better than she could.
With Rhode there was always an extra level of jealousy that coursed through Aphrodite. There was that sea queen who had claim over her as mother and it cut through Aphrodite, Aphrodite who adored her children so fiercely. Rhode would never fully belong to Aphrodite so have that Titan witch here, throwing her magic around, was a slap in the face.
Besides, Aphrodite just didn't like Hecate.
Aphrodite had heard Rhode's words as she reached the room and told her, "you're never alone, dearheart." Her eyes then passed to the Titan, icy in their glance. The urge to say something biting was there, but Aphrodite held it back.