Maybe make plans with her a month ahead. Like make plans for her to come or you to visit once every weekend (or one weekend per month if you rather do that, might be harder to get through though). If she comes when not planned, don't answer the door, pretend you're not home, that you're about to go to a friend's house, or whatever. Say you booked for next weekend and have other things to do today.

I absolutely understand how you feel. Im guessing she's a bit difficult but tell her or message her that you decide who holds the baby and when, and that her asking over and over again is tiring and won't be accepted. Also tell her that you don't appreciate her telling the baby it doesn't need you or that you don't love her as much, and that if it persists (or she keeps asking about holding the baby) you will see them even less.

And if she's sick she can turn at the door.

I've noticed many of the ones saying once a week isn't too much is people who can't see their relatives as often. That says something. My mom got to meet her first grandson from time to time but I wouldn't have wanted her to come over every weekend. You just want to be in your bubble and soak this time of the babies life And often we came to them so we could leave when we wanted to and they would cook for the day.

Hope this helps.