Not the momma, Well then who is?

How do I get my teen to respect my position in our family?

Long story short, we have custody of my step-daughter, she is 17 years old and I have been in her life for 10 years. In our house I have been the primary caregiver for all of our children. I do all the running for games, practices, all extra-curriculars, doctors appointments, etc. I also work full-time and pay for our health coverage and food. Her biomom does not work for a living, she does very little for her child. She has in the last 10 years been 2 maybe 7 events. This past season she has been to 1. The only game she came to was a homecoming game that they were going to announce the kids parents names at half-time. Mom threw a tantrum with stepdaughter telling her my name should not be announced because I am not her mother. I’m use to that mentality from her. In any event my step-daughter was upset by her mom’s outburst which bothered me, alas all parents names including moms boyfriend were announced. Mom however showed up to said game late, then left as soon right after they announced the parents names. Several times recently my step-daughter has asked why her father and I refuse to meet her mother halfway so she can visit for a weekend and really became bratty about it. My step-daughter is having issues with her periods, I’m not sure if she has even made her mother aware but she is uncomfortable speaking to her dad about it and spoke to me about it. I have told her several times that she needs to get with her mom about taking her to the doctor. I’m sorry but at this point if she wants to continue to say I’m not her mom she is then I feel she needs to do what moms do. How do I get this point across to my step-daughter without saying negative things about her mother.