I read a novel about 10 years ago about a girl who somehow finds herself on the homeworld of aliens. I don't remember how or why she got there.
The aliens used I think sonar since they were blind, and I kinda think they communicated with telepathy too. The girl noted about their strange architecture, with a dull gray palette but very interesting shapes, as a result of their sonar perception.
Towards the end she I think enters either a black hole or a wormhole, to change the speed of time. I don't remember why she did that - all I remember is her watching time speed up faster and faster for the aliens in relation to her, and that she was going there for some sort of goal. There might've been some element of self-sacrifice involved with this - I recall it being done solemnly. I think a few of the aliens might've carried her there, though I'm not sure.
What was this story I read?