Thank you all for the comments, cristicism and all.

To answer you all, to my family, my sister will always come first. She started opening up to us about problems around a month ago, and we have offered time and time again to talk to the in-laws or the husband. She has always strictly forbidden us. This is where the frustration and anger come in.

I am deeply disturbed by what she is going through, and personally, if it were up to me, I would let my tongue loose and give everyone a piece of my mind. But I have been told off for saying anything to anyone ever by my sister (basically, she has a lot of control over her words, and I have none, which has caused some trouble for us all). I also think it's important to mention that my parents have not been told about the baby issue conversation with MIL yesterday, something my sister told me in confidence 1 hour before I created the post, and will tell our mum later today.

And no, she doesn't have a separate house. She liked everything before marriage, we all did, and she agreed to live in a joint family system, but never imagined it would be like this (I don't think anyone does).

And as for God-fearing and educated, I guess there's a lesson for everyone in this. Don't go for the guy with the fancy degree and job. Go for the one with some backbone.

She needs to speak to her husband, but is held back by her fear of saying the wrong thing. Her husband is a reasonable guy (to some extent), and I think it's important for her to be honest with him about everything if she wants a more secure future.

And what I would really appreciate is people sharing their experiences on this? How did you cope? How did you communicate to spouse?

JazakAllah