Perhaps you can have your husband talk to his mother? He is in a better position to tell (or telll off) his mother for allowing all this hectic visitors even though you have just given birth.
Also, perhaps you and your husband can tell your MIL that all the visitors coming in and out may not be good for baby's health. Since baby is sooo young, baby's immune system is not strong enough and all that people activity might cause baby to fall sick.
You can also suggest a party of sorts for family members and friends after a few months -- for now, tell her you and baby (especially baby) need all the rest you can get.
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