God: "I looked for someone to take a stand for me, and stand in the gap" (Ezekiel 22:30)
God displays righteous jealousy (cf. 2 Cor. 11:2) that desires faithfulness from His spouse. If God cared not for His people, there would be no jealousy. But it is because He values an intimate relationship with His bride, the church, He is deeply grieved when we pursue other lovers. True love is rightfully jealous. God loves His people so much that He wants us totally for Himself in an exclusive relationship. He will not stand for spiritual adultery.
Wherever we find the Word of God surely preached and heard, and the sacraments administered according to the institution of Christ, there, it is not to be doubted, is a church of God.