What was the relationship between Adam and Eve?
Eve was Adam’s wife. God formed her from one of Adam’s ribs and brought her to him. Genesis 2:21-22, 25
What the Bible says
Genesis 2:22
And the Lord God built the rib which he took from Adam into a woman: and brought her to Adam.
Genesis 2:23
And Adam said: This now is bone of my bones, and flesh of my flesh; she shall be called woman, because she was taken out of man.
Douay-Rheims Bible (Challoner revision), public domain.
What the Church teaches
God created man and woman for each other. They have the same dignity and form a communion of persons.
Catechism 369; Catechism 372 · Catechism of the Catholic Church
Did you know?
A note in an 1836 Bible explains it this way. God did not form the woman from the man’s head, nor from his feet. She would be neither his master nor his slave, but his companion. Torres Amat note on Gn 2, 22