Complex sentence: Once she disappears, we begin to learn the secrets of every member of the family and friends; the paranoias start, histories from the past, themes that were supposed to be buried and the recriminations among family members start.
Split into simpler sentences: Once she disappears, we begin to learn the secrets of every member of the family as well as those of her friends. Paranoia sets in, the past is dragged up, matters that were supposed to be buried reappear and recriminations among family members start.