Your boyfriend is right. Remove the fluorescent fixture(s) and install whatever lighting you want. Beware, though, of hanging pendants in front of a mirror. For each pendant you hang, you will see two. And be sure the pendants don't obscure your ability to see yourself in the mirror when you're standing in front of it.

A couple of options: have the unit replaced with LED potlights within a new "box" constructed of drywall. Or replace the unit with a tube LED fixture. PS: are you sure the bullnose tile in the shower ends where it butts up against the light box? Or is it hard to say without exposing the area first. Just curious.

IMO that light box is just attached to the ceiling and is hideous remove it redo the ceiling and put in what you want for lighting

The shower tile DOES end where the lightbox begins, unfortunately, so you can't rip the lightbox out without retiling the shower. I've considered replacing the until with potlights. And I'm 5'4", so I don't think I'll have to worry about any pendants obscuring my view. :) Thanks everyone for the feedback!

Until you're ready for a much bigger undertaking, you're stuck with that notch in the shower. But I don't think you have to be stuck with the whole 6 feet of soffit that attaches to it! If I had to choose between having lights hang out of this box, or having a little piece of drywall down at the end after I ripped the rest out (and put in the light fixtures I wanted), I'd do the latter in a flash. Would give a few minutes to thinking about what might make that notch look intentional, like maybe screw an air vent cover onto it for kicks, but then I'd patch it up and move on (while secretly planning my dream shower overhaul, heh).