Originally posted by: Eternalallure
She is getting married to permanently close those doors. So that she cannot ever go back, and viaan can never come back. It's actually viaan's presence that pushed her to take this extreme step. Aarav's just the catalyst. Because he likes the guy and objectively they make a good match. When did she decide to marry? When she learned that viaan was coming back and saw aarav still wasn't well. When did she get engaged? The day Viaan got out. Why did she decide to push the wedding ahead? Because she saw that Viaan wasn't going to give up and had coincidentally found a way back in her life too. Honestly, the best way to escape would have been to move to another city and start afresh, instead of using another man as a crutch to keep your ex away.
Katha's reason to break ties with Viaan is her fear that Aarav will get to know about ONS someday if they are together and that will push him to guilt for a lifetime. In the car driving scene, she has explicitly told this. He may take it as he was the reason behind the ordeal his mother has to undergo. We can not even imagine how his life will change if he gets to know the truth. So its a huge risk to keep Aarav and Viaan together.
Now the ONS is not a secret between just Katha and Viaan. And she has seen how that broke two families. So her fear is justifiable. If Maya or Teji can get into the deep of ONS, what is the guarantee tomorrow someone else will not make Aarav know about it. You never know anyone who is aware of this can turn against them and use this.
But her strategy to get married to Raghav is to hold back herself from getting affected by Viaan's presence. She wants to block the path. And her getting married to Raghav is more foolish as it will break two more people later. She has not moved on, but wants to show Viaan that she moved on thinking he will also move on after that. She is using Raghav to show that she has moved on and through that she is shielding Aarav.
The problem here is Katha is thinking and acting like a mother and Viaan is acting like a lover. There is a clear conflict of interest. Katha also loves Viaan, but she knows that they can not be together for the future of Aarav. And Viaan is not thinking that way. Katha is basically choosing Aarav over Viaan. And thats natural.
The best possible solution in this situation is to have open communication between Katha-Viaan, and Viaan also will agree to Katha in this case. Later She can move in to a different city and stay away from Viaan. Otherwise, Katha-Viaan-Aarav after resolving conflict between Aarav-Viaan can move in to a different city or country and live away from their past relations. Even then there is a risk involved in it.
I believe the route they are taking like Katha trying to keep Aarav away from Viaan is more relatable in Indian scenario than the OG turkish one. She is representing a typical Indian mother trying to protect her child from everything.
In my personal opinion, Katha and Viaan should come to a point of peace and part ways and move on in their lives.