[Ah. That clearly didn't help him. Maybe he even made things worse. These are condolences he's heard used before, but whether he's doing it wrong or he's just so different from everyone else he's known it doesn't comfort him he's not sure.]
I'm sorry. I don't really know what to say that will help you.
I'm sorry....
I'm sorry. I don't really know what to say that will help you.