Yeah, it doesn't sound as if your internship is going particularly well. A job - especially the wrong job - can really wreak havoc with your life. Personally I rarely minded the work itself; it was the people and the politicking that got to me. (

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As a matter of fact, MatBell, your description of leaving work early reminded me of something very similar that I did once. The people at work always ignored me too, and one day when they were all over at the supervisor's desk laughing and talking, and ignoring me as usual, I got so angry that I just plain got up and left. I just left work. I didn't even tell anyone, I just got up and left work an hour and a half early. This is so totally not like me...
When the supervisor finally noticed and called me at home I made up some cockamamie excuse about having given blood that day and become disoriented as to time, blah, blah, blah, (which was actually true about the giving blood part, not the disoriented part) and so I got away with it that once.
But if I hadn't been massively pissed and upset I would never ever have done that. So I definitely feel your pain....