When and where did the church become the 'Bride'???
We are betrothed to Jesus at time of salvation.
2 Corinthians 11:2
For I feel a divine jealousy for you, since I betrothed you to one husband, to present you pas a pure virgin to Christ.
Revelation 19:7–9
Let us rejoice and exult
and give him the glory,
for the marriage of the Lamb has come,
and his Bride has made herself ready;
it was granted her to clothe herself
with fine linen, bright and pure”—
for the fine linen is the righteous deeds of the saints.
And the angel said to me, “Write this: Blessed are those who are invited to the marriage supper of the Lamb.” And he said to me, “These are the true words of God.”
Matthew 9:15 “And Jesus said unto them, Can the children of the bridechamber mourn, as long as the bridegroom is with them? but the days will come, when the bridegroom shall be taken from them, and then shall they fast.”
You can find this anology also in Mark 2 and Luke 5.
John 3:27-30 “John answered and said, A man can receive nothing, except it be given him from heaven. Ye yourselves bear me witness, that I said, I am not the Christ, but that I am sent before him. He that hath the bride is the bridegroom: but the friend of the bridegroom, which standeth and heareth him, rejoiceth greatly because of the bridegroom’s voice: this my joy therefore is fulfilled. He must increase, but I must decrease.”
Ephesians 5:23 “For the husband is the head of the wife, even as Christ is the head of the church: and he is the saviour of the body.”