My sister and her husband have 3 daughters, 14, 10,and 7.
They've always done their best to foster healthy relationships between the girls, encouraging them to spend time together as a group and one on one.
Despite this there is some sibling rivalry, what I too would deem a "normal" amount, so if their parents are not behaving like the enemy you described, nor modelling any of their daughters into the enemy, who exactly is to blame here?
These are 3 well adjusted, loving, kind and intelligent girls, who sometimes behave as rivals, something I've seen in every family to a certain extent, where parents weren't frucking up there kids left right and centre...
I'm sorry for what you went through, but I get the feeling that because of that, and also your journey to healing, you tend to project and also generalize a lot where parent-child relationships are concerned.
That is to be expected of course when one lives through a heinous childhood, but I wonder if leaving some room for a difference of opinion or a different perception may not be of assistance toward you.
For example, what if your children display some normal rivalry, would you then assume you were a horrid parent, the enemy, that you failed your kids?
I would certainly hope not.
Because even though siblings can grow up loving eachother, we don't always like eachother, sometimes our characters are wayyy too different and its really hard to get along. Sometimes we wouldn't befriend some family members if they weren't family because they're "not our type" but we're forced to when we're young, because of the simple fact that they're family...and yes sometimes we compete for brownie points, attention or whatever, doesn't mean our parents frucked up and did a halfass job.
Just my 00.02, I'm hoping you're willing to make use of some of it.