My guess, and interpretation of "seeing the guy next door and we're an item now", is that the condom in p31 split apart, meaning that Lars accidentally knocked up D.W - but either of them know yet (probably)...
...and in a bid of jealousy and/or desperation brought about by her urges, Jane throws herself upon Lars and thus history from p27 repeats itself...
My guess, and interpretation of "seeing the guy next door and we're an item now", is that the condo