While playing the main quest, I got bored with the Enclave after escaping from Raven Rock and went to Point Lookout.
Did all the quests there, but now (for roleplaying purposes) it kinda bugs me that my character took months before getting
back to the Citadel to report there and take back the purifyer.

Does anyone have an idea (roleplaying purposes) what could have motivated my character to head for PL and keep them
waiting this long?

Whenever you play a series of quests, do you finish them all the way before starting other quests? Or do you just start/play
whatever quest you feel like?

Thanks in advance

Since the characters in the game wait around for me to solve their problems instead of fixing it themselves, then they can wait for me to show up. I have left my father for game months hanging out in Vault 112, I have left other parts of the MQ hanging for even longer. Sometimes I ignore the MQ completely. That being said, I do tend to finish a quest section or stage up before I go wandering off.

As for PL, you can role play that you ate a Punga Fruit at the dock, then went on a psychedelic bender on the island and got caught up in the events over there.