Long-time wife immediately wants to move out and take her husband's ring because she's uncertain if he'll go back to the woman he cheated on her with long ago (as they'll now be working together by chance)? Why not just divorce instead of the ridiculous preamble? If it's a "test" by her to see if the MC will be tempted to cheat... then she can fuck off quite frankly. Yeah, I understand Nasira being a little worried considering past events (and of course you can choose to cheat on her if you want) but she jumped to an option that could signal the end of their relationship too.
She wouldn't even be able to complain if she sees that he hadn't cheated on her and decides to move back in, only for him to reject her return. She wouldn't be able to blame anything on him in that instance.
(Cheating is an awful thing to do but it was shown that their relationship survived it and they had supposedly moved on, only for his wife to immediately break down in paranoia the moment the other woman pops back up into their lives.)
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After re-reading the section... it's even dumber than I thought. He didn't "technically' cheat on her at the time. She's indeed testing him despite not wanting a separation, divorce, or an open relationship. I don't know any woman who would go this route in real life, but this is a porn game after all.