To each its own.
But it's absolutely couple dynamics in their situations and circumstances. Honesty and truth are very important in any relationship n not just between partners. People fall in and out of love at the drop of the hat today. Play behind backs and make a mockery of their partners and relationships. Which is absolutely not worth. So I would still respect two people who are honest enough to accept their shenanigans and mutually decide to share a roof than over someone who chooses to live a dual life.
For me trust is important in any relationship. Initial love will always fly out of the window when the rainbow subsides and challenges of life befalls. It is mutual understanding and the faith in your partner that will help one to go a long way. Therefore I hate lying and fake promises. These factors r termites and no matter how deep the love be, they are going to chew on the foundations causing the structures to fall. This is my problem with Raghav too here. His actions are the time bomb waiting to blow away the foundations of everything he has built with Pallavi.
Personally I am a kind of a person who will not be okay with infidelity no matter physical or emotional. It IS a deal breaker and I am NOT okay with it.
However, emotional infidelity is more dangerous than physical one I believe coz emotional gaps acc to me always get filled with toxicity which suffocates either one or both the partners.
But then again, it's easier to see and comment being an outsider. Being into a situation is probably a completely different thing and no one knows how s/he will actually react when in a spot. Feelings, emotions, level of involvement and at times societal pressure make people act completely out of their basic nature and one can never understand the underlying motivations. That's why I would not want to judge anyone's choices and actions.
It's important to remember that we built an idealistic world in our heads, however, we don't stay in one!