We have four kids at four different schools with two different custody schedules. Not to mention piano, tutoring, soccer, cross country, basketball and two girls playing tennis. He and I both will probably spend at least eight hours in the car this week carpooling kids. Every week is tough logistically, but I am proud to say we are surviving.
Unless you are truly an "evil stepmother" (and there are some), releasing expectations of acceptance and love from your stepchildren will allow you to focus more on your partner, building a strong and lasting union, which certainly benefits the kids who don't need to go through another horror of a family splintering in different directions.