Reading your other questions she sounds like a controlling step mom. Then I read this, your kids think she walks on water? Kids tend to be loyal to their parents unless their parents give them reason to run, they drive them away.
I am concerned because it sounds like you really don't know how to handle this at all and you are actually driving them right into her arms with your actions.
I am saying it sounds like your heart is in the right place but you need help! Professional help. I am not actually sure what form that would take. This isn't exactly a mental health issue yet I think a psychologist would be the best help. Not because there is anything wrong with you but that they would be able to explain the result of your actions, how they are working against you. They would also be able to give you a working plan to fix it without harming your kids or their relationship with their father.
I sometimes think people don't realize that although we are irrational creatures we are mostly all irrational in the same way. An outside observer like a psychologist can say I know you were going for X but they saw Y and reacted......
In light of Leigh's response that I mostly agree with, I feel I should add about steps. My kids, even the adult kids, prefer my husband over their own dad. He actually disciplines them more than their dad does he loves them and wants them to be viable members of society. My ex is evil which is strangely not my point, my ex is insecure and drives them away. If they do not spend every moment with him telling him how wonderful he is, how much they love him, obey every stupid request like hand me the remote, he goes off about how they don't love him, they love my husband more, they only want to take from him, use him. Although I am sure this is not how you behave around your kids I just wanted to point out that you can drive your kids away. This is why I recommended an outside observer that understands emotional dynamics.
Oh sorry, forgot my point, my ex calls my husband and I every name in the book to the kids. It only makes them defend me, it doesn't make them think he walks on water. At least in my experience and that of my divorced friends, things like they are the Disney parent, or they talk bad about me, are just things that are said rather than figure out why you think the kids love the other parent better. I say think because in many cases the kids treat the parents the same but it is the parent's issues that drive the perception of preference. Then the parent reacts to the false perception and it becomes an issue of self fulfilling prophecy.