Step moms: advice for adapting to your role as step mom
Their mother is the one who gave them life, who's always there for them, who loves them unconditionally, who dries their tears, who washes their clothes, who mends their broken heart, who is never disloyal to them, who has the right to shout at them without being judged, who prepares their favourite meal and who consoles them about your presence... at least that should be the case.
Step mums shouldn't try to compete with their step children's mother and never speak badly of her. If you do have (genuine) grievances with her, don't discuss them within earshot of his children. Don't exclude her from their life, even when they're at your house, that's the quickest way to turn them against you!
Dominique Devedeux points out that: "The mother of your step children cannot be replaced. Whether you think she's a good mother or not, she has a supreme status that step mothers simply can't compete with!"