And outside of the main plot, there's like... quests that end in such a way that it's like they forgot how they started.
Blood Ties starts for most people when Lucy West asks you to check on her brother. You go to Arefu, and find that it's locked down because a gang called The Family has been terrorizing them worse than usual and even killed their only cattle. The West mother and father were killed, and you have to search a bunch of places until you find the right subway tunnel with The Family. Despite a lot of their incidental dialogue indicating that they just view themselves as a "tough gang," the leader reveals that they're actually cannibals with some kind of psychological compulsion to eat people. You're instructed to "educate yourself" about them, and learn that they pretend to be vampires and only murder select people to drink their blood. Oh, and the killing of cattle thing was just stuff getting out of hand. The Wests were actually killed by their own son, Lucy's brother, who has THE HUNGER which is a thing that exists in Fallout now I guess.
As the "kill the fucking murderous vampires and free Ian" thing is glitched to make Arefu hostile the quest a failure, the only real solution is to negotiate with Vance, the literal vampire man. The game suddenly acts like this cult of murderers is an oppressed minority of dangerous fanatics like the X-Men and Vance is their Charles Xavier, which makes sense since he's a brainwashing jackass. Depending on your skills and stats, you're given like four ways to ask, "Have you considered just drinking blood from the blood packs that are everywhere and not murdering people?" Vance reveals that he thought of this, but didn't really care too much until you brought it up. Turns out, you're going to negotiate a deal on Arefu's behalf! This malnourished, isolated little hamlet will donate their fucking blood on the regular and the heavily armed cannibal gangsters who terrorized them will leave them alone, or even guard them if you've got a silver tongue! Some might call this "extortion." Fallout 3 calls this a wise choice filled with good karma.
Ian West can go home, or not, and you're just left to assume that his whole "I have a mental illness that causes me to black out and murder and eat people" will just work itself out because you talked to him kind of nicely.
Lucy West can never be told about this, and any attempts to talk to her will result in her saying something like, "Oh yeah, I asked you about my family, eh they're probably fine."