Looking for emotionally devastating recommendations on angsty espionage fiction with profound moral conflict and heartbreaking sacrifices the mc has to endure. (What am I for, if not to suffer?)

I crave espionage fiction full of angst, moral ambiguity, loyalty twisted like a blade, and the slow, suffering of a protagonist caught in the crossroads of betrayal and duty.

It's better of the protagonist realises nobody's "good" or "bad" and that they are slowly becoming the monster they saught to destroy and feels kind of attached to the people they're forced to betray. And how they survive (or don't) being crushed by the war to save others.

Any fellow seeker of pain and suffering?