An ocean-shaped or a polymer-based "lifeform", while formidably uncanny, are still somewhat fathomable.
What about a radio-waves-based "lifeform"? Or a star whose plasma interactions are so complex that some form of artificial "life" emerges within it?
Lem's narrative is indeed intellectually teasing. And, yet, critical of our approaches and behaviors as a species.
Lem's work (at least Solaris) explored the intellectual inability of our species to communicate with a vastly superior intelligence. Solaris did not have any problem seeing what people were doing, thinking, signalling to it, and so on. It's just that what possible difference could it make?
Another fantastic book on the subject His Master's Voice, where a whole massive team of scientists tries to decode an interstellar signal. In the end, they didn't even prove it was a signal, and not a natural phenomenon.
Also - The Invincible. Probably the most western sci-fi styled book among his works, dealing with an interesting concept of mechanical evolution.
On the topic of self awareness vis-à-vis aliens, Peter Watts' Blindsight is a recent classic.
Close enough? https://en.wikipedia.org/wiki/Dragon%27s_Egg
IIRC in that, the communication difficulties were due to clock speeds not mindsets.
There must be a list of fictional alien races living in stars, but i couldn't find one with some quick googling.
It might object to you dropping a lead-line into it to do so, though.