But to answer seriously...
This has been argued by Christian theologians as a reason why God exists in Trinity - in relationship.
But on the topic of girlfriends, if man and woman are made in the Image of God, then it follows that God is female as well as male. He does not need a complimentary life partner because He is complete in Himself.
Is this reflected in the Genesis myth of God using a rib from the Man's body to make the Woman? Who knows, eh?