Matlockitis

The acute onset of loneliness, sadness, and boredom resulting from living at one's parents' house during the summer vacation when one would usually be studying in a thriving and happening city during term time. The risk factors of catching the disease include one's parents living in a small town in the middle of no where and one's friends being able to still live in the city.

Dad: You're looking a bit down, are you missing your friends?
David: No it's worse than that; I think I might have Matlockitis.