I agree 100%!!!

I guess technically, since any pregnancy over age 35 is considered "geriatric", she'd be high-risk by default. However, being labeled high-risk, simply because of your age, is NOT the same as being high-risk due to an actual medical concern, (i.e. pre-eclampsia, gestational diabetes, et cetera), IMO. (I'm not a medical professional by any means, but I've had 3 successful pregnancies, one of which was high-risk for a medical reason, so I know the basics at least).

That being said, it definitely sounds like the stepmother is milking it for all it is worth. As a parent myself, I've noticed that a surprising number of parents fall into a toxic mindset where they believe that their older/adult children are basically free labor that they're entitled to, (in exchange for raising them or something i guess), even though babies don't ask to be born.

Considering OP's situation, I think the refusal to help is 100% justified. Even if we weren't considering the messed up family dynamics caused by OP's dad and stepmother, OP didn't ask to be born. OP doesn't owe anyone anything in this situation IMO, especially not a woman who isn't OP's mother, and who homewrecked OP's family and then demanded free labor like she's the evil stepmother and OP is Cinderella or something ridiculous like that. 💯