Man, Donna's arc in the series is one of those bittersweet side stories that really stuck with me. She wasn't just a throwaway character—her disappearance actually revealed a lot about Don's flaws. After their passionate but messy fling, she just... fades into the background, much like how Don treats people when they're no longer useful to him. The show never gives her a proper exit, which kinda mirrors how disposable relationships can be in that high-stakes world. I always wondered if she left the city or just became another ghost in Don's past.
What's fascinating is how the writers use her absence to highlight Don's emotional detachment. There's a scene where he walks past her old apartment, and you can see him hesitate for half a second before moving on—classic Don. It makes you realize how many 'Donnas' must exist in his wake. The lack of closure feels intentional, like the show's saying some people just vanish from your life without explanation.