A working definition of Sinat Chinam (Baseless Hate)

Sinat Chinam is when you distance yourself from someone, not to protect yourself, but because you find them distasteful.
When there is someone that is doing something wrong, and you rebuke them, and they don't change, you are allowed to hate them, but you also have to love them.  You hate the part of them that is doing something wrong, and you love their inner Neshamah.

from the Shiur on Naaleh: Destruction of  Unity - The Three Weeks

Teacher: Rebbetzin Tziporah Heller Class: Maharal Netivot Olam IIhttp://www.naaleh.com/viewclass/224/single/