Meerab could have left at any point, any time that family humiliated her. She did not. She chose to stay and let this marriage work its way out. That was a choice she made, and she’s been vocal about wanting this marriage to work out. But she couldn’t give in completely despite her choice, and thus her issues throughout the married life. She chose to come back every single time. She even kept her ego aside to return for Maryam’s rukhsati, which was in reality she returning for Mk.
She stayed there because as she herself said she had no where to go. She never was interested in the marriage working out or not untill she had an infatuation for murtasim. As it's is said, with every right comes a duty and the 'duty' one has in a relationship is to put some efforts, and acknowledge the other person's efforts too, but Nope, all we got were some non sensical, discontinuous romantic scenes in tits and bits, which look good but when put together make no sense. I am not saying that she had to carry the whole weight of the relationship on her shoulders only, but atleast she could have thought of murtasim as a team mate, who too was forced into this marriage.
The above was for the episodes after their marriage.
For maryam's rukhsati track, I actually admired her for trying to mend their relationship, but again that ship sank and at that point I genuinely felt bad for her, but not for long as the makers decided 'oh people are sympathising with her, let's turn the audience down again' and here we land up with the most selfish side of MEERAB none of us never imagined. Questioning the people who are taking care of you without asking for anything in exchange, and concealing the pregnancy news from the father of her child, so not done!

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