How we cite our quotes: All quotations are from Vertigo.
Quote #1
MADELEINE: I love you too … too late … too late.
When "Madeleine" says this, Scottie thinks she means it's too late because she's doomed by the spirit of Carlotta to kill herself. What we don't yet know is that this has all been a scam to cover up a murder. Once we learn that, we can see that what Madeleine really means is that she's too deep in the murder plot to ever be with Scottie.
Quote #2
SCOTTIE: The only important thing now is that I love you, and I'm going to keep you safe.
Scottie's fallen hard for Madeleine, and his promise to Madeleine is much more tragic for being impossible to keep. Other than the fact that she's beautiful and mysterious, what's so mesmerizing to Scottie about Madeleine? He really knows nothing about her; she spends most of their time together staring off into space. We suggest that it's because can imagine anything he wants about her and make her into his fantasy woman. It's kinda like why it's so easy to get infatuated with someone you only know online. You can project all your desires onto them and never have to see them in messy everyday real life.
Quote #3
JUDY: If I had the nerve, I would stay and lie, hoping that I could make you love me again, as I am, for myself.
That's just what Judy does after tearing up the letter in which she confesses her deception to Scottie, but Scottie won't love her as herself. His obsessive preoccupation with Madeleine limits him to trying to recreate his relationship with Madeleine via transforming Judy. He's unable to have a sexual relationship with her until she becomes Madeleine. He's lost touch with reality by this point.