Haven't yet seen the episode (it's on DVR, waiting for the wife), but you're dead-on about the weirdly hostile and often show-killing nature of the 'shippers'. They are the idiots who ruined Law and Order: Special Victims Unit by obsessing over whether or not Stabler (a married father of 5-10 kids) and Benson would get together, which slowly but surely turned the show into the Benson/Stabler Adventure-Romance Hour (when's the last time Munch left the office? 2006?). They are the scary people who actually angrily confronted Rashida Jones on the street because she was coming between Pam and Jim on the second/third seasons of The Office. They are the ones who cared more about who was sleeping with who on House as opposed to what medical mystery needed solving.
And, most importantly, they are the reason why I can't look up any remotely well-known song (especially a ballad) on YouTube without finding a bunch of horrifying fan-made romance montages about Angel and Buffy, Kate and Sawyer, Benson and Stabler, Lois and Clark, House and 13, and every one of the 4,000 possible combinations available on Grey's Anatomy (a show I blame for so many shows turning into a 'who will she choose?'/'when will they get together?' soap opera). Go ahead, I dare you to look up any decent Sarah McLachlan song... see what pops up. The horror! The Horror!