I feel something bad happening to HS physically might trigger Babita to take up a wife's role.
I'm just assuming that she has never known anything except doing seva. So cooking food for him and taking care of his things covers that. But she's never received any rights from her husband so she basically doesn't know what rights she has.
I mean that Babita will never initiate the intimacy part cause
1. She has never done that
2. She simply doesn't know what it is about
Simple words mein jis rights ka humein ata pata nahi hai, usko hum exercise kaise karein? She's only familiar with duties and not the other way round.
I think it'll proceed like
She will have desires to be close to him (like pottery scene), HS will figure that out and he'll probably initiate, maybe force her to some extent and then it shall kick off.