She can forgive the person who committed such a huge mistake of betraying her love and trust but not an innocent kid Veera. What is Veera's fault?
It was Sampooran who is the root cause of all her troubles and miseries, not Veera.
But Ratan has closed her eyes and don't want to see the reality because she is envy of Veera as Ranvi loves Veera more than he loves Ratan.