I'm not an "official" step parent yet, but I'm in a long term committed relationship, so pretty much the same thing.

My partner has pretty much sole custody of his 2 kids, boy age 9, girl aged 6, because their mother is unfit (mentally, physically abusive etc). He was abused in the marriage, and besides the mental scars he has, both kids have VERY hard to deal with anxiety issues.

The 9 year old, remembers Mommy beating Daddy, and hiding under the bed. Right now they only go to their mothers on the weekends, but there is so much harmful stuff going on now, it's really affecting them. He has terrible tantrums/fits of rage/self loathing/fear triggered by things that remind him of his mother (aka his father says something to disipline - not in anger - but it's something the same as his mother says, the poor thing has a complete meltdown).

The 6 year old girl is the opposite. She seeks out attention any way she can, she lies all the time, she tries to control her friends (which no doubt she gets from her mother) and has an overall, superiority complex, mixed in with self-esteem issues.

Both kids have been seeing a child psycologist since right after my partner left his wife, and thank goodness for that because court is coming up soon to try to get some child support from her for them, and to try to get her weekend visitations away from her (mostly).

I find it so completely mentally exhausting to keep up with all this, drama. There is always so much going on. Some of it is normal things that children do, but a lot.. is not. On top of that I'm an emotionally sensitive person, and I'm working on my own issues as well. Just curious if there is any advice from anyone here who is dealing with similar issues. Thanks!