Maybe this should be in AIBU because I probably am, and I feel terrible about it.
My MIL was/is lovely. I always liked her and I always felt lucky to have her as a MIL because you hear some in law horror stories don't you?
But since having ds2 (ds1 from a previous relationship) I can't stand her. In the days after he was born, she kept coming round to the house, kept dousing herself in perfume so ds2 would "know her smell". But really all it did was make him come back to me smelling horrible, not like my baby at all. It seemed that all I got him for in his early days was for pain as he had tongue tie and feeding him was an excruciating, blood and tear filled experience. As soon as I'd fed him, she'd want "her cuddles". If I tactfully tried to ask for some alone time to try and get bf established, she took it as a personal judgement that she didn't bf! (she told dh this).
I spent days after his birth crying, especially when my milk came in and I couldn't even wear a top. So I hid upstairs while dh ferried ds to me for pain for feeding, and then back to MIL for her fucking cuddles.
Why couldn't she just wait another week or two? I didn't properly bond with my baby for 2 - 3 months and I blame her (though maybe it was the difficult feeding start so I am prob BU with this too)
I did tell dh to have a word but he is too bloody soft. I already feel like she doesn't like me anymore, like I'm chopped liver - the obstacle keeping her from having her precious grandson whenever she likes.
She keeps trying to create situations where she can have him alone. Why does she need to be alone? I keep saying no, he's bf, what if he's hungry etc.
When ds cries she keeps saying he's only doing it for attention, she doesn't mind crying, and she thinks I'm batshit for feeling upset when ds is hysterical. She wakes him from naps too. 
She doesn't have any bad intentions, I don't think. That's why I feel so awful for feeling like this. It's got to the stage where I bristle when she comes near ds. I've asked dh to have a word with her re: the constant crying comments and waking him up, but he hasn't. Meanwhile this resentment is building in me and I'm afraid I'm going to explode at some point. Oh, did I mention we are staying at her house for a week right now? hollow laugh
It seems it's quite common for people to have MIL problems after having a baby. Is there some psychological reason I can use to rationalise it?
At the minute I'm trying to think of a good excuse to go home from this week at her place, early.