Once on the court, she had the right to interpreter the law.
I'm not sure what you are saying. If you are saying that because the Supreme Court has ruled on Roe v. Wade, that is it now the law and cannot ever be changed, I don't think that is correct. In the 1890's, in the case Plessey v. Ferguson, the Court ruled that separate, but equal, schools for black and white children were constitutional. That ruling was finally struck down by Brown v. Board of Education.
That being said, I don't think we can expect to see Roe v. Wade significantly altered during my lifetime (I'm 53) but I do believe it will eventually be altered to allow each state to decide it policy on abortion.
That appears to me to be clear thinking.