When a marriage starts to break down, the way you respond may not always be the most logical approach. Some people tend to withdraw from relationships when they can see that the end is near. You might choose to leave the family home or start taking more travel assignments at work, thus limiting the amount of time you have to spend in a tense household.
Unfortunately, this approach can be particularly problematic for the parent who pulls away from the family. The courts could very well give primary or even sole custody of your children to your ex as a result of your withdrawing from the family unit.