Setting aside Monk's been over for at least a year, considering he lost his job because of his obsessive behaviors (and some more resembling paranoia than compulsions) and required a PA to function outside the very tightly-controlled conditions of his home, I wouldn't say it was entirely portrayed as a 'cute quirk.' Especially as it was played as initially a high-functioning situation made severe (ie the needing help to leave the house and stay calm, the need for consistent talk therapy with a professional) by his wife's murder and some of the obsessive behaviors stemmed from maintaining her things exactly as they were. OCD is not strictly a disorder where someone washes their hands until they bleed (hand-washing may not even be one of the behaviors.) Ritual and repetitive behaviors can become destructive without needing to be 'doped to the gills' to get out of bed in the morning. IOW, TV may not be accurate (I think the trend of making light of and/or glorifying sociopathy is probably a lot more destructive) but your sister's case is not a typical example of an OCD patient, either, but rather an extreme one. Some obsessive and/or compulsive patients can learn to function without medication and still have a legitimate problem.