I think this is a good answer, but a couple of suggestions. I wouldn't go a lot into trying to explain autism. Why you find social encounters draining really doesn't matter. The issue is that they are very tiring for you. Also be persistent. Her initial response will probably be denial / questions. Just repeat that you find social interactions very tiring and you need to take a rest break. The good result from this is that even if she says that she doesn't believe you, when she sees you heading to the couch, she'll have more info on why you are moving over. — DaveG 1 min ago

if you have a list of the previous college's research students and just want to find which one is hers have you considered searching the names on social sites (eg. Facebook, LinkedIn, Instagram, etc)? — BKlassen 22 secs ago