Calling all bonus (step) moms

My bonus (step) daughter(7 years old) for these purposes we will call her C lives with my husband and I full time. C has a complete dead beat for a mother. My issue lately has been that her egg donor never does anything for her and is always letting her down. And then we she does the smallest thing for C, stuff a normal parent should be doing anyways C can't stop talking about it. She will not talk about anything else for weeks on end. And yet my husband and I never stop doing really great things for her. I don't need recognition, that's not what I'm looking for. It's just so emotionally draining. I wish her idiot mother would either do the things for her that she should be doing and do it all the time or just fucking disappear. Don't show up once in a while with a $4 mcdonald's meal so you can remain on your pedestal. Do your fucking job as a mother like I do and I don't even have to and move along. It just suckssssssss. Can anyone relate?