OK, revision.
Turns out the daughter is only upset that I'm sleeping over already. She needs some time to get used to it.
She said she really likes me and she thinks I and her dad are good together and she wants to see us continuing to go out and build the relationship.
Guess I was upset enough to hear that I couldn't stay over (especially since I was absolutely exhausted from being on the water all day and the last thing I wanted to do was drive almost 45 minutes home), that I twisted her reasons around in my head.