My heart goes out to you, it's not easy being a step-mother. I have 3 step-children and they are grown now. I've been in their lives for 5 years now. The youngest was 14 when I married my husband. They used to think badly of their Dad, many of the same reasons you listed and more. After many long talks with my step-son, it took awhile, but he has figured out his mother and her lying. He's 22 and she's still lies about everything. I've told him, he needs to just accept her as she is and respect her because she is his mother and let the lies go in one ear and out the other. It won't take long for the kids to figure out whats going on. PM me if you want to chat.