How did everything change when edmond returns to marseilles after 13 years?

When Edmond Dantès returns to Marseille after 13 years, he finds a city transformed by his absence, where his former life has crumbled. The people he once knew have changed, and his loved ones have moved on; Mercedes has married another man, and friends have become enemies. His return ignites a desire for revenge against those who betrayed him, marking the beginning of his quest for justice and transformation into the Count of Monte Cristo. This pivotal moment sets the stage for his complex journey of retribution and redemption.