What is your worse betrayal? Why?

My worse betrayal was by my younger sister. While I was pregnant and stay home, my ex husband and my younger sister traveled a lot with their band and always on the road. While traveling away from home, they developed feeling for each other and ended up sleeping together. My ex husband was cheating on me with my younger sister. I found out later my younger sister got abortion twice.

What is your worse betrayal? Why?
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