Alfred Hitchcock famously (and creepily) said, "Blondes make the best victims. They're like virgin snow that shows up the bloody footprints." (Source)
This guy enjoyed working with coolly elegant blonde actresses that he could put through mayhem in his films. And Tippi Hedren was no exception.
One of the most famous scenes in The Birds is when Melanie goes into the attic and is nearly killed by a flock of bird attackers. She thrashes and spins and gasps, bloodied and increasingly panicked. The scene is highly sexualized: Melanie moans, shudders, and calls out for Mitch. It's almost like a Leda and the Swan scenario.
After the attic attack, Melanie is traumatized and almost catatonic. She's gone from an impeccably dressed and coiffed socialite to a ravaged, disheveled victim.
Now, reread Hitchcock's quote. Creepy much?
Art Imitates Life … or Is It Life Imitates Art?
Tippi Hedren and others on the set have said that Hitchcock was controlling and abusive in his relationship with her, and even pressured her for sex.
The attic scene was itself extremely difficult and uncomfortable. Although Hitch had promised to use mechanical birds for the scene, Hedren had real birds tied to her clothing. She suffered cuts, injuries, and psychological distress that put her out of action for a week.
If Melanie is being physically assaulted in this scene, it seems to parallel Hitchcock's own emotional assault of his star.