What do you call a wife or woman who knows their spouse or partner is unfaithful but pretends either to (1) not care or (2) to not know? In this scenario it's important that the cheating spouse or partner believes his wife or partner hasn't found out. That he is having one or more love affairs without being caught.
I did manage to unearth an archaic term wittol, which The Chambers Dictionary defines as
a man who knows his wife's unfaithfulness, and accepts it.
The Collins English Dictionary online says:
a man who tolerates his wife's unfaithfulness
[C15 wetewold, from witen to know (see wit²) + -wold, perhaps from cokewold cuckold]
I'm curious if there is a modern-day female version. I can't think of any off-hand and yet I'm sure we all know someone in our lives who has knowingly accepted their partner's infidelities be it for religious convictions; a sense of loyalty; pride; love; fear of loneliness; fear of hardship or merely motivated by social status.
A modern literary example:
In Gillian Flynn's novel Gone Girl, although the beautiful pro/antagonist Amy Elliott Dunne is fully aware her husband has been cheating for over a year, she pretends not to know and is far from being acquiescent. Only the reader is privy to that information.
(I realize it doesn't match the description perfectly, but it's important that Nick Dunne is unaware of his wife's discovery.)