Erin,
I have almost the same situation as you. When first day went back home after delivery, i want to latch on char but my mil keep carrying her and don't allow me to carry at all. when she cry i want to carry her, again she don't allow me at all. I got very frustrated and cry, then becos she started on bottle feeding my girl which i can not latch her at all cos char will scream if she drink no milk, at tat time my breast milk haven arrive mah.
I got very stress up and depress, so i never breastfeed during confinement at my mum's hs.
After that full month must bring char back home mah so i bring lor want to put her in her playpen and sleep, my mil see her crying then carry her out to sofa and sleep with her. Ok lor i bare with it. Then after i went back to work only bring char back home on weekends mil still don't let char sleep in her playpen, she make her sleep in the rocker. OK lor i keep quiet. I bare with it. She can even only feed char water when its time for her milk feed. Then when char around 4 mths mil start feeding her milo, ice-cream, coke and so on. After which she develop rash, i stop MIL told her later She sick or what u going to pay for her medical feed?? So now she knows she is allergy and don't dare to anyhow feed her liao.
when char was 4mths plus she is learning to flip liao so i told mil that she cannot sleep at rocker later she will fall, and now sleep at rocker is uncomfortable. thats when char start sleeping in her playpen.
Got once Stupid MIL bring char out without letting me know. At that time she likes to anyhow feed her things.
Now she can only carry her and play with her other then that feeding, bathing, sleeping, going out must be with me around.
Even she open our room door and see char i let her see let her play with her. i don't mind, sometimes when i busy cleaning char bottles and refilling boiled water, i will ask mil to carry her.
Erin, Sometimes u got to let go abit. At least u see your boy daily, i only see my girl once a week and its only fri sat and sun. think the other way round your mil help u carry ur boy you can do ur stuff like bath, changing clothes to prepare to go to work. Don't stress yourself over this small matter. Ur mil loves your boy thats why she also want to spent time with him ok?
LIke when its time for your boy to go to bed you go to your mil and tell her nicely time for him to sleep and just carry him back yourself, don't wait for her to carry to you.
Thats what i do, when char crying that means she want to sleep i will carry her back myself and put her to sleep.
Hope your problem can solve