why is medea given the status of God towards the end?

In the Theban plays of Sophocles, the gods help even Oedipus to achieve a kind of redemption. Those Gods don't operate on an established human value system, they like to shake things up. The Chorus sings that the gods have had their hand in these events; yet how or why is anyone's guess. Medea establishes the Euripidean universe, one in which heroism is rare, the gods are at worst malicious and at best absent, and suffering falls on the innocent and the guilty with equal brutality.