Dan a fait une dépression après que Linda l'ai quitté.

Shouldn’t it be "…que Linda l’A quitté?

Indeed it should be.

Fun fact about French people. As the locution “avant que” is more often used than “apres que” (in general) and that the former is used with subjonctif, people tend to use subjonctif with “apres que” instead of indicatif. I guess the one who wrote this sentence made the mistake :slight_smile: