The natural biological bond that exists with your own children is not there with step children. The nurturing instinct is transferable, but never as intense as with natural children. This is complicated by the inevitable tensions and stressors inherent in step parenting. Loyalties to the biological spouse break down the coparenting needed to run an orderly household. “You are not my real mom (dad)!” is a common refrain to attempts to set limits. The estranged spouse may have a hidden agenda to undermine the new household. Try as you might, you just don’t attach the way you do with your own kids.
For step parenting to work, you must put aside all these issues and strengthen you bond with your current spouse. Remember, a child needs a structured and orderly household to grow. Never sacrifice this to make a child feel more loved. Practical efforts must be made to stop undermining effort from exes and the adults need proper venues to deal with their own feelings that do not interfere with parenting. All must put this as first priority. A regular meeting with all adults is useful.
It is important not to fall into the trap of acting out your own needs and frustration through parenting. This is exaggerated with step kids. Weekly(or daily!) strategy sessions with your spouse can help. If your own feelings are to strong, seek therapy. Always keep in mind we are responsible for the safety and well being of all children under our watch until they can truly care for themselves!