Biological mom had ALS and passed away when baby was 1 year old. I’ve since met this woman who my daughter calls mommy. We’ve been together for 1 and 1/2 years now. At first she was all over her and now my 3 year is wanting nothing to do with mommy. Doesn’t get excited when she comes home. Doesn’t try to interact with her much at all. Mommy is the disciplinarian and I’m not as hard on her. I work and am gone 2 weeks at a time. I don’t understand what happened? What do I do to help the situation? When do I start telling her that she has two moms?
This most likely has nothing to do with the fact that Mommy is not the biological mother of your daughter.
All toddlers have periods in which they are attached significantly more to one parent than the other and don't respond as much to the other parent. Most likely your daughter has such a period in her development and will grow out of it in a couple of weeks.