I think that's the point, he could have a meaningful, sensual, sincere relationship with her if he tried, because she knew him, knew what he was about, what drove him, she was fascinated by him as a person because she could relate to him, his greedy selfish nature is what keeps driving her to figure him out, and he keeps brushing her off, pushing her out, annoyed, almost bewildered by her keen ability to put 2 and 2 together.
In a way she wants to lend a helping hand, but he himself, he's afraid of honesty, integrity, he's afraid of actually being truthful, living a truthful life. Denying her and denying himself is the footnote in his behaivor. He doesn't like the honest nature of her, and the fact she sees him for what he is, since she can see him for what he really is. He pushes her away. An honest connection with an honest woman isn't part of his nature.
If you have some sentiment towards the actress for playing quirky, eccentric roles then I can see why you'd be disappointed for her only 2 scenes or how many there were.
But I thought her character was brilliant, and I only recognized her from The Killing about halfway into the movie, and I thought it was awesome to see her play a more subdued, calm, existentially oriented character as a opposed to the sassy, fast talking, selfish person she plays in The Killing.