They were not. Athena was a virgin goddess and goddess of heroic deeds.
Athena was a virgin goddess, she had no lovers.
Athena gave Perseus a polished shield, and Hermes gave Perseus a sword to attack Medusa with.
No one acted as a mirror for Perseus. Athena's polished shield acted as a mirror for Perseus though.
Odysseus and Perseus
Athena
No, they did not marry.
Grover and Athena.
Athena and Hermes
Athena and Hermes
Athena
When Perseus gave Athena Medusa's head, she put it on her shield.
Athena's demi-god siblings are Helena, Perseus, and Hercules.