It's annoying when some NPC's are waaay too possesive, usually you can just go back to the conversation by ignoring the interruption and the NPC will go back to talk to another NPC, but some do interrupt constantly. It is why I prefer playing with 8 characters, and only 5 being girls, so more relationships form and they leave me alone (while still letting me cheat from time to time). I've found also adding an evil NPC helpful, but it is kind of a roulette since it can start kidnapping characters too early.
I find having over 3 relationships going at the same time exhausting due to the constant interruptions, but anything below that seems to be OK.
