I know God created us with the means to have sex and bear children so within a marriage it is pure and good to God but when Eve was tempted (or seduced) by the serpent it “opened their eyes” and they then became as one of the immortals “knowing good and evil” and then they “knew” that they were naked, felt ashamed, and hid themselves. God stated that there would then be enmity (strife and hatred) between HER seed and the SERPENT”S seed. Cain killed Abel. Didn’t God say to Cain something to the effect that he is like his father the devil? Then he said that Eve’s desire will be ONLY for her husband and she’ll have children in pain. I cannot believe that all this change and punishment (even death) is based upon eating a piece of fruit. I think it is figurative.
enmity between
It's not because they ate a piece of fruit.
It's because they disobeyed a direct order. It's because they were prideful enough to demand the knowledge for know;edge's sake.
The act was merely a symptom.
It was not so much the fruit, which yes was a piece of fruit, but the fact that Adam disobeyed God. It was rebellious disobedience that caused Adam to fall out of divine blessing and into the curse. He now had the knowledge of evil. Now he knew what it meant to not trust and obey The LORD which is what evil is. It is possible that you cannot really comprehend good unless you know what evil is.