I sometimes look at my abusers social media
Why be hard on yourself? Doing that just brings back bad memories.
It makes my blood boil with suppressed rage and the impulse to kill
There's no need to remind yourself of pain and abuse. Tell me more and let's remedy your situation.
The abuse and pain was necessary to be a better person in the end. The memory is as faded as a bad dream yet the trauma is ever present.
Stop yourself from pain shopping and stop all the contacts with your past abuser. You are letting him win by always thinking about that person.