You have no idea how hard it is to look something up when you don't remember the title of the show or most of the character names. So I'm going to provide as many details as I can:

I watched the tv series back in the late 90's or early 2000's. The main character is some middle-aged guy who can see ghosts. He is attending these meetings to cope with his condition and he wishes he could 'lock it and throw away the key'. He also spends quite a bit of time with an obese black woman named Michelle.

At one point, he comes across the ghost of an old black woman named Helen from Idaho, asking him to pass something along to her granddaughter. He later finds out that Michelle is her granddaughter.

He has a bizarre dream where his mother wakes up from a hospital bed and follows the ghost of his grandmother (her mother). He keeps trying to speak to her, but they don't hear him.

Another scene, shows him at a police station, reporting a theft after his car is broken into. He encounters the ghost of an old man, who is the deceased husband of another women there. Later, he confronts her and reveals that her husband died of a heart attack while being mugged, after the mugger stole his heart medication (effectively making him a murderer). With the help of somebody at the department (after some difficult persuasion) they track the mugger down.

He is continuously disturbed by the ghost of a young black boy, who he kindly asks to go away. The ghost coughs up a constant stream of dirt. With the help of a Ouija board, he finds out that the ghost is of a kid named Dennis. Dennis' subtle clues and hints lead him to a remote place in the woods where many murdered children are buried.

I think the season ended with a bunch of ghost children found in the back seat of his car reaching out to him, indicating that his nightmare isn't over.