Most upsetting interview rejection?

Back when I graduated college, I did the usual rounds of interviews with insurance companies, banks, various other institutional businesses set up by the college's career center.

One local insurance company interview I thought went great. Usual 'Where do you see yourself in 5 years?' type questions, told her about my job history, very high level type stuff.

Couple of weeks later I get a letter in the mail and after the usual 'It was great to meet you blah blah blah', it ended with
'State Farm will never consider you for a position with our company.'

Never?! My then fiance (now wife) yelled "WHAT DID YOU DO?!!!" and I racked my brain for anything I might have said or done. The HR lady was attractive, but I didn't stare at any body parts and I didn't make any weird sexual advances (I was nervous enough without *that* going thru my mind).
The college career center floods the local companies with graduates and I was #5 in the waiting room that day. My only guess was they got me confused with someone else.

My fiance wanted me to call them immediately to straighten out any misunderstanding, but I knew what was done, was done. It's not like they would realize "Oh, that's right, it was Bob that kept looking at Karen's breasts, not you...come work for us!" Besides, why would I want to work someplace that didn't know/care who I was?