I felt that way all the time in collage, I feel for ya, its nice to have your own personal space, and boy do we need it!! This is why I live alone, I much be alone half the time.
I know its hard, but try to mingle a little, you dont want them to think you dont like them. People have a hard time understanding us, I know, but as soon as its over your roommate will eather be happy with ya (and I think she owes ya) or she will be angry with ya that you were not nice.
I hope you wokred everything out with your roommate prior to their arrival, I always hated visotors if I was not prepaired.
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DX'ed with HFA as a child. However this was in 1987 and I am certain had I been DX'ed a few years later I would have been DX'ed with AS instead.