This is only a guess, but to me "Air Pressure" means the constant pressures and stresses of life (like how the atmosphere imposes Psi's on us at all times). If one takes the game literally a relationships is another air pressure we deal with. A more symbolic interpretation might be that we live so long under a atmosphere we get used to the pressure, like how the protagonist had gotten use to his addiction(rather drugs or self mutilation) and it doesn't truly bother him any more.
P.S Mister Bento Smile, if I am sorta right or completely wrong tell me please
 "Book of Mages: The Dark Times"){kind=icon}
 "Doodle God"){kind=icon}
 "Relive Your Life"){kind=icon}
 "Save the Moon"){kind=icon}
 "Memoir Text Adventure"){kind=icon}
 "Air Pressure"){kind=icon}
 "Canabalt"){kind=icon}