Thanks for playing, we're happy to hear that you enjoy it!
The game will end after five years regardless of hangout status, unfinished personal quests, etc. There are many more main events and characters than can be seen during a single playthrough since we designed the game to be replayable yet refreshing (and even encourage multiple playthroughs). So if you feel like you're up for another playthrough, it's completely fine to not do all hangouts for all available characters, since you can just get them again in another playthrough. But if you only want to play the game once and want to see as much of it as possible, you should consider doing all the hangouts and personal quests that you can, since as previously mentioned, the game will be forced to an end after five years.