Why does Islam obligate a son to gain his parents' approval of his wife, and do parents have the right to control all their children's affairs?

The questioner's issue concerns the parents and their relationship with their child. Islam has given every rightful person their due, thus differentiating between rights. Among the established rights of children is their legitimate right to choose a life partner. The child is not obligated to obey his parents in marrying someone he does not desire or divorcing his wife at their command. However, if they forbid him from marrying a specific woman, the default is that he must obey them, unless he fears falling into haram (definition), or the prohibition is out of stubbornness, or the son would be harmed by not marrying her. It is better to prioritize honoring one's parents over one's personal desires due to the reward involved and the strengthening of affection.