Aphrodite's Links
Aphrodite doesn't really talk to Apollo outside of formal affairs. She doesn't think much of him, but respects his position as a powerful prophet.
Since he's had visions of the past, he knows Aphrodite and he's past lives were in love with each other. While he's in love with Aphrodite's true soul, he knows both of them have changed too much to be together again. That doesn't keep him from longing for her from afar, though.
He's always fighting an internal battle on whether he wants to get closer to her or stay as far away as possible.
Aphrodite takes great care in upholding her appearance, and feels angry when she's perceived as anything except beautiful. So, the fact that Athena believes her to be the epitome of beauty, no matter her appearance, made her fall in love with Athena.
Also, both of them like watching mortals killing each other. So that's something. lmao
Athena is absolutely obsessed with Aphrodite. Athena couldn't care less about conventional definitions of beauty -- she finds beauty and pleasure in violence, evil, and war. However, Aphrodite, who perfectly embodies beauty as a concept, deeply appeals to Athena. It's like horseshoe theory, where she loves war and bloodshed so much that it somehow loops around to her loving love and beauty, but only in its absolute state (AKA: Aphrodite) and nothing less. She fell in love with Aphrodite at first sight.