passing without obstruction

alienation; estrangement; leaving (someone) out; casting out; cutting off; avoiding; giving the cold shoulder

underpopulation; low population density; depopulation

evacuation (to the country)

estrangement; alienation; neglecting to stay in contact

sparse; thin; scattered; straggling; sporadic

(reciprocal) communication; (coming to a) mutual understanding

empty (e.g. argument); insubstantial; hollow; fruitless

negligent; neglectful; careless; remiss