If it's a choice between the mother's life and the baby's life, because of the medical condition, I would say let the mother make the choice.
But if it's a choice between the mother's feeling / opinion and the baby's life, I would say the baby's life overwrites the mother's feeling / opinion. The reason is simple, nobody gets to decide to kill the other person just because he/she doesn't like it. And the existing of the baby is the consequence of the mother's behavior.
The only exception is the that the conception is a result of rape, in this case the conception is not a consequence of the mother's voluntary behavior. But I still struggle with this, because the baby does not become less human because it's a result of rape.
I don't think there is a valid choice between someone's life and someone's feeling / opinion. And remember, pregnancy is something totally normal for women to do. And many women do several times in their life. It's not a punishment, nor a definite suffering or torture.
Also the "nobody else's business" argument is wrong, murder is the government's business.
As for when is the OK time to conduct the abortion, this is the question for people who support abortion. I don't really see the point here. The development is a continuum process. I don't believe there is a definite cut point where the humanness changes from zero to non-zero. Even when it's a embryo, it's a human embryo living in its natural environment, with the full potential to grow to a full human. I also don't see the need of a spiritual concept like soul or whatever.
Typing the above paragraph leads me to think about lab-grown human embryo. Google leads me to this webpage: https://www.nature.com/articles/d41586-021-02343-7 "Researchers are now permitted to grow human embryos in the lab for longer than 14 days." Of course I don't believe humanness changes from zero to non-zero on day 14. Also I don't believe it's ethical to experiment on some human to gain knowledge to save other human.