Grandmother Overspending on Newborn

Grandmother won't stop buying things for newborn grandchild. I've told her to stop a million times. I appreciate everything, but for one, stuff is starting to accumulate and there's not much room left, and for two, I'm afraid all the money she's spending will lead to her having entitlement issues. She's never had any respect for boundaries, "no" always means "yes" and she also has a problem with "as long as no one sees, it's fine" ... so I will never leave her unsupervised with the baby because of that attitude. She can't follow rules. Should I just let it go? The baby isn't here yet, I'm 38 weeks, it could be my horomones, but it's realllllly annoying when I constantly set a boundary and it's just shrugged off. I know it's her money to do with as she pleases, and I could probably use the extra stuff or just throw it in a closet, it just bugs me to feel disrespected and not heard. She can come off as being really self centered when I try to have talks with her about respecting my boundaries. There's literally no talking to her. She has selective hearing and is very stubborn. She undermines me a lot.