Sometimes when things go bad, they go bad fast. My wife patiently smiles at me when I fantacize about owning a porsche boxter. Did you know it will go 0-60 in 4.85 seconds? Cool and exciting but there is nothing cool or exciting about your's or your spouses rage going 0-100 in .85 seconds.
In stepfamilies mired in high speed conflict, blending is most likely not happening. Rage or unchecked anger is a seperating agent. You might have legitimate reasons to be angry but when anger turns destructive it will not serve you in making needed change happen.
I think this happens out of desperation many times. A husband feels desperate to bring order or discipline to his new home and the stepchildren were not raised the way he believes they should have been. A wife knows her children have been through a lot so feels the need to protect them from their stepfathers discipline. Anger gets revved up like my fantasy Porsche but this is no fantasy and it hurts everyone involved.
As long as your anger goes 0-100 everyone will maintain a posture of defensiveness. This is presented in many forms. The kids will become defiant or just hide in their rooms or because they have learned to tune it out will simply look apathetic. Your spouse might try to appease at first and then hammer his/her own accelerater to 100 rages per second. Either way what was legitimate about your anger has long faded into the background (rearview mirror?).
The way to a blending family, a healthy growing family, requires a much slower, safer speed. Most likely whatever led you to rage in the first place truly is legitimate. In remarriages, these issues are more complicated than what you feel they should be. Trust me on this, they are-and as a result take longer to resolve or to work out compromises.
Sometimes they require outside help. I encourage you to invest in real help sooner than later. My dad had his own autobody repair shop. Cars that were wrecked were either driven to the shop or towed in. A simple lesson for me was this: the faster the car was going the more damage it had from the wreck and the more damage, the longer it took to repair. I was always amazed however after my dad finished the last coat of paint.
Give your marriage a chance for success. Take matters that cause anger slowly. Your angry feelings can serve as a caution to soften your tone and slow your reactions. Patience is far more apt to move all of you to blend than desperate rage. With slow, gracious strategies taking you through complicated remarriage and blended family matters, you will someday look at your family and be amazed.