Who comforteth us in all our tribulation, that we may be able to comfort them which are in any trouble, by the comfort wherewith we ourselves are comforted of God. For as the sufferings of Christ abound in us, so our consolation also aboundeth by Christ. Include your spouse when making plans concerning the children. Make sure to set time aside for your spouse. Even if your spouse is not your children's biological parent, your children need to see a strong marriage.
Strong marriages make strong families.
You'll be surprised how much resentment will be extinguished from your children's hearts. Please don't turn a blind eye to the problems in your household. Your children should know without a doubt that you expect them to respect your spouse. If your spouse's ex is spitting mad that you have entered the picture, you're in for problems no matter how much the children like you. Children are very loyal.