One thing is crystal clear. Meher is crying today not because Akshat gave her the ultimatum. But because if she accepts it she would need to let go of Abeer. And if she doesn't accept it then she still has not stopped loving Abeer. She is in a catch 22 situation.
So thanks to her wish to move away from Abeer she would accept it. If you had watched IPKKND you would know what I am talking about. There Arnav wanted to get into a loveless marriage because he wont be hurt that way. So he wanted to steer clear of Khushi who seemed to be turning his heart inside out and make him feel vulnerable.
Meher is sailing in the same boat, if she accepts Akshats proposal she would be safe. But that wouldn't make her stop caring for Abeer. But going forward her feelings for Abeer is going to intensify.