One more important point I wanted to mention:

Try to see both the good and the bad side of the person from your past: My father hit me countless times, sometimes to the point of me wetting my pants in front of family and the maid. But, he enjoyed taking me to watch games, and we also enjoyed watching games together on TV. He was also great in taking care of both my Mom and me if one of us were to fall sick. I still remember him bringing me water in the middle of the night, from about 20 years ago or more, and staying up the whole night at my bedside.

Anyway, the point is, once you see both the good and bad in someone,
1 - They begin to seem more human (and hence more "normal") and less monstrous.
2 - It becomes possible to realize that they didn't only have bad intentions in mind for us. They, perhaps, also wanted good things for us.
3 - How much we differ from them seems to lessen, because we have flaws too.

I can see why Marsha Linehan based her whole DBT program on this simple yet powerful concept - the dialectic.