Do not allow yourself to think of the abuser, the relationship, any aspect of your past while out of your safe zone. Anything that comes into your mind must be obliterated.
This can be done by training yourself to immediately look at an object when you think of the Abuser/Abuse.
For example, you are at school or work. A memory comes into your mind. Immediately look at anything which is permanent; it could be a tree, it could be a light fixture, door, anything.
Focus on it.
Teach yourself to automatically look at your object as the thought slips into your mind.
This is vital.
This prevents you from being distracted, confused and captured by your past. Focusing on the Now is survival.