Why does the end of School Rumble have to suck so bad? *spoilers?

I just discovered the anime School Rumble a while ago, and found it to be one of the funniest and at times one of the most touching things I've seen. But holy crap the end of the series is matched only by the Titanic disaster in terms of stunningly beautiful creations meeting a horrific demise. Not one good thing happened to anyone. Tenma ends up with Karasuma, but he's a near-vegetable who can't remember her. Harima winds up a wandering hobo. Yakumo not only doesn't get to be with Harima, she also doesn't get to be with Tenma. Eri ends up alone. Good God don't make me go on. Can this crappy ending be defended in any way? Did anyone NOT hate it? Is there any possibility that it's all just a terrible head-fake like the alien ending in the first season?