I'm never "happy" with a loss, but I have the feeling that if the Cs had won this game, a lot of players would be thinking (at least on the subconscious level) that they can do this sort of thing all the time—that is, play like crap for large chunks of a game but then "flip the switch" just in time to pull out the win. And that would be a very bad thinking habit to develop.
As for Monroe, I know that most of us love the defensive identity of this team, but you still need reliable sources of offense, and IT is the only guy on this team who can be depended upon to put up 20+ just about every game. Bradley's a pretty good shooter, but he's not a shot creator; Turner's a pretty good shot creator but a terrible shooter; and everyone else is either streaky or doesn't get enough minutes/shots to be big-time scorers.
The ideal player is great at offense AND defense, but those guys are rare, and some folks around here may have to relinquish the idea that every Celtic has to be an above-average defender. Monroe (like Love) would at least be big contributors in scoring and rebounding, and that's nothing to sneeze at.