It features Bruce interacting/coexisting with the Hulk (or at least trying to), and is on Archive of Our Own (ao3) somewhere, but is NOT "Irreconcilable Differences" by determamfidd, I've checked that one.
All I have is a small amount of text from a screenshot I took a long while ago:
Hulk smiles at his pattern and stands up, stepping over it to walk to the other end of the room and break a boulder apart with his hands, piece by piece. Love not always good. St. John love Jane, but Jane not love St. John the same way. That love made Jane sad.
You read Jane Eyre?
Felt sad for Bertha. Mr. Rochester mean to Bertha.