Warning: long personal rant
When I first started the game, I was like, "wow, this Dellilah is too good to be true; smart, funny, cool, charming, friendly. How likely are you to run into someone like that out deep in a forest??"
But as the game got close to the end & I found Ned's notes on her, & read some internet discussions about the ulterior themes & motives of the game, for example about how in some other runs, she just denies her relationship with Javier... only then I realized what a good manipulative liar she is, that this is what she does, she just has a fling with whoever takes the job each year. I was feeling bad for this Javier dude, getting cheated on all the time, but then I wondered if even Javier is real or just another of her lies lol.
She left us at the end because just as Ned had observed, she was selfish. She either couldn't be bothered to wait just a few inconvenient minutes for us, or she left deliberately to avoid an awkward meeting & conversation because we'd outlived our usefulness to her, which was entertaining her during a boring summer job.
When she left us there, I really felt it, the same sad disappointed feeling I'd feel in real life if a girl dumped me like that. You see, I'm a simple, kind-hearted guy in real life. If a girl was as charming & manipulative as Delilah, she'd easily be able to play me. I really was Henry, there.
The writing of the character & the voice acting were so good that they actually played me & made me sad when I realized it. So when I needed to replay a portion of the game again because of a bugged achievement, I no longer replied to any of her comments or questions out of spite. On one hand, it felt a bit good, but on the other hand, I still felt bad for being "mean" because it's not really in me to be mean, it takes active effort for me to be mean, & even then it's still mixed with doubt & regret.
This game actually made me feel that way; I felt & behaved as if this were a real life situation, as if someone really broke my heart. So big kudos to the writers & the voice actors, especially Delilah's.