.
Don't think he will doubt her character. It will not be him. They have too much of understanding to even doubt it. However he will definitely feel whatever he does she will never love him. Might even think about leaving her.
If he feels he never been good enough for him coz it's always she who has to protect him an that she deserves better or maybe he feels she still loves Zain and for her sake he decides to leave her then I am okay with it but not otherwise.
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