Why are social mores stronger than dating and potential love?

I am white. Back in high school I had a black girlfriend. The school faculty said we looked "cute" together. My father was NOT happy. But when he found out that her parents were middle class, then he changed his mind.

Her father was over protective. I do not know if it was my skin, or the fact that I was from a poor family. Anyway, we did go on a school trip out of state together (it was a group of 12 students and three teachers). We still studied together. If anyone asked, I said, "She is a girl and she is my friend, and that is all".

Today I am married. My wife is not white. I was born in LA. What can I say. We California kids are open minded.
Added (1). Her name was Barbara. Please excuse me for referred to her as my "black girlfriend". I used the label for clarity, not out of any disrespect.
Added (2). Typing on an iPad. Excuse my typos.
Added (3). Her family was middle class. That means they owned a house. We rented a trashy mobile home with a leaky roof. She was not wealthy.

I am edicated, but I paid for it myself.
Added (4). Still typing on my ipad, sorry. "Educated", but not good at typing on a tablet. Haha

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