Yeah pallo would prefer to chain her son to a girl he doesn't love rather than allow him to be happy with the girl he loves because with the former option she feels he would stay more subservient to her rather than his wife if he marries a girl he has no feelings for. That's awful considering that is not the kind of woman either of the kohli ladies had been presented as. They forcefully brought this typical change to pallo just for drama.
Ranbir going against her for a girl, shocks her the most. Well writer need villains in Pranbir story, so they have to make one family member against them. Who could be better than Pallavi.