Safeena was lady Kabir Singh, so she was just happy to have Murad back, just like Kabir Singh was happy to get back Preeti even accepting her kid(which he thought was her husband's, as he didn't knew it was his).
So these are common traits in these type of toxic masculinity characters, they don't care about world, if they want something, they want them regardless of anything.
See justification, depends on how you view it. Safeena was a person who just wanted Murad, and didn't saw or didn't want to see any fault in him, that is why she always looked to blame others for his mistakes. So when you know that character is like that, you don't see that situation justifying cheating, it just shows that the person is a mad one, who doesn't care about anything if it means they get what they want. And it wasn't like Safeena was a submissive doormat, as in their relationship she was the one who wore pants. So you cannot say the she did it because of society pressure. So when a confident person takes his/her decision, it isn't justifying. Justifying is when movie shows how a woman shouldn't leave her husband, no matter what, thus she attempts to get him back, ala Biwi Number One.
But here it was completely different.
Kumkum Bhagya
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