Actually, God divorced Israel and gave her a certificate of divorce (see Lamentations and Jeremiah).
So that kind of blows your "Jesus was free to marry another" theory.
Were the Jews part of Israel?
Were there Jews in Jesus' day?
"Therefore, my brethren, you also have become dead to the law through the body of Christ, that you may be married to another—to Him who was raised from the dead" (Romans 7:4)
Was Paul speaking to Jews?
All Californians are Americans, but not all Americans are Californians.