Yeah, I KNOW he's a ghost! But surely he would have realised something was up way before he found out in the film just because no one has talked to him ever since the shooting.
When he's lying there in hospital recovering presumably his wife is blubbing away, yet he can't cheer her up and can't even get the attention of the nurses who for some reason keep putting the sheets over his face.
So he feels a bit better on his own and seeing how everyone is ignoring him he decides to check himself out, but the nurse on the desk just keeps ignoring him too. How rude! Steps out into the street to get a cab home, but no one will pick him up! So he walks.
Gets home: "Hey honey!" Nope she won't even look at him and she's pretty upset. "Want to talk about it?" Apparently not. Ho well just knock that on the head then.
So he goes to meet his next case. Knocks on the door. Haley Joel Osments mum opens the door looks all about "Hello? Hello?!" "Hi I'm.." Whoa she nearly shut the door in my face!
"Hi I'm here to sort your kiRAB problems out. Hey! I said "I'm here..." Ok lets go and sit down. "So how's he been? Yoo hoo!" (waves hand in her face). The kid comes in: "Hey Bruce! I see dead people" "Oh thank God! I thought my acting was so wooden that people were mistaking me for a grandfather clock or something." "Nope I can see you. You and dead people." "Phew!"