a. when ansh kidnapped nadhine, tulsi told mihir but what did he do nothing.
b. when tulsi told the mihir and the family about mohini what did they do they got haresh and mohini married.
c. when tulsi told mihir and family about vishal murder and what did they do they got shobha married
so i think that going by the above happening i can understand why savita asked tulsi to do what she did.
i think that tulsi did not want to see her mother suffering and that is the only reason that she what she did.
i wonder if savita told the police who tried to kill her.