In the second third of the novel, Gabriel Garcia Marquez uses repetition of events. From my perspective, the reason why Marquez uses repetition is because the characters itselves are always remembering what their old lives used to be before technology was introduced to Macondo and also before the war. The arrival of new groups to this village have changed the Buendia's family so much that they are stuck living in the past. Like Mary said, "repetition in life of all Arcadios, Aurelianos, Remedios, Amaranta, etc" proves the point of how the family is and will always live in the past.
Also, I agree with steph and her observation. Macondo was a small village where no one has ever died and now Macondo is a war erupting city where many have died. As for Ursula. She is the only that still represents the old Macondo with its beliefs and culture. While everybody else got caught up with technology and power. For example, Jose Arcadio Buendia, her husband. Now he is spending the last years or days of his life tight to a Chestnut tree as all his family falls apart(89).