Mr. Monk and the Actor - S5-E1
Corrected entry: Monk tells David about Trudy's murder, saying she told him that day she was going out to run an errand for his brother Ambrose. But this contradicts the facts established in "Mr. Monk & the 3 Pies," where Monk didn't know why Trudy had gone out that day until Ambrose told him. That's definitely not a fact that Monk would get wrong.
Correction: Given that Monk "found out" several times that Kelly street was not an address one must assume that his memory is not very reliable when it comes to Trudy's murder and everything surrounding it.