Mr. Monk Meets the Playboy - S2-E8
Dexter Larson: I was the kind of guy that a woman like you never talked to.
Sharona Fleming: You still are.
Mr. Monk Meets the Playboy - S2-E8
Noelle Winters: Is your wife here?
Adrian Monk: I'm not married.
Noelle Winters: You're wearing a ring.
Adrian Monk: She passed away. I can't bring myself to take it off yet.
Noelle Winters: Oh, I'm sorry. When did she die?
Adrian Monk: Six years ago.
Answer: Notice also that in the opening credits scene when he is touching parking meters her also wipes his hand on his clothes each time he does it.