This episode made Andy look like a complete asshole. I genuinely don't understand why they would make him behave that way, and how they expected us to react. We didn't know Jessica well, and there as no reason to be invested in that relationship, but that doesn't make her deserve that humiliation, or make her friend deserve to have her bachlorette party ruined.
This was my reaction as well. They needed to give us some reason for the urgency of Andy's breakup other than wanting to sleep with Erin for it not to come off terribly. Since they couldn't be bothered to make Jessica an actual human being other than "Obstacle blocking Andy and Erin", trying to make that last scene at the cabin seem romantic strikes me as almost sociopathic.
If I may, while more hurtful to Jessica and disruptive to the bachelorette party, Andy screwed the pooch when he didn't defend Erin's character when Jessica mentioned - in front of everyone - the terrible things he said about her while he and Jessica were dating. If she had accepted the "I'm Gay" excuse or hadn't mentioned how Andy said that Erin wasn't marriage material or whatever it was, then Andy and Erin could have happily run off into the sunset. But somehow the public "You said Erin sucks" (to paraphrase) really needed Andy to step up at that point and not only defend Erin but also flat out admit that he and Erin were indeed and possibly always sort of were in love.
Maybe its old-timey of me, but if you want your relationship to suceed, you kind of have to enough guts to at least openly admit your love in front of a hostile crowd, particularly if the crowd thinks your love is an idiot or sub-par.
I actually felt worse for the awful magician - although Pam and Jim's sabotage of his act was cruelly funny.