There are many kinds (can't name them all off the top of my head)
1. Telling someone you'll keep it a secret and then tell anyway...
2. Always being there for someone and then not
3. When you cheat on your husband/wife or someone you're in a relationship with
4. Using someone just to get some
Those are all I can think of (at the moment). But you can just pick whichever one you want.
To determine the root cause of contamination
He is disgusted and shocked by the identical lower caste people.
She is focusing more on her work, she is stressed from her deadline and puts all of her attention on her work
