I've had a rougher time of it than I expected, blending in with this new role. I wish I enjoyed it more, at times, than I do. It's not easy developing the love and bonds with other people's kids...
I think overall, I need to build discipline and grace. To accommodate more of other people's needs and opinions, observe more, talk and struggle less.
If I can become more flexible, I know this will all ease up...it's just so hard to handle the emotions that rise from crossed boundaries, uncooperative attitudes and hostile exchanges. I hate to see children treating each other with disrespect, but the siblings seem to really have a lot to bicker about. They don't get along with each other as well as they seem to get along with my daughter, but I think that's because she doesn't share their history or issues that have come from the environment at their mom's house...it's a hostile one, for sure.
I feel sorry for them having to watch her and her current husband fight, sometimes she gets hurt and it must really rattle the kids...to the point where the only thing they know to do is react to each other. Safer than reacting to the adults over there.
The result is some young people that can make the home a very unpleasant place to be because there is constant yelling, crying and name calling going on when they're here together. Hard to love them through it, but that's exactly what needs to happen. That and firm boundaries around our treatment of one another in this house.
Sentences written repeatedly seem to work:

I will treat others with the respect I want them showing me.

I will use age appropriate language.

I will appreciate what I have without pushing for more.

Whatever the issue seems to be that arises, a task of about 50 sentences like one of these seems to focus them and nip the behavior in the bud.
Then it's up to hubby and me to develop enough discipline to hand the consequence out gracefully instead of in frustration...after all, it's supposed to be their problem dealing with the consequences of their actions, not us taking it on so heavily...I think.
Grace always seems to get better results than frustration or anger...it's a challenge we try to meet every day.
Then, we all shake it off, watch a family movie or go somewhere together and try to enjoy being the blended family, instead of the pureed one. :)