I think sometimes the issue simply has to do with the other person. I'm thinking of my MIL, who is extremely sociable, to the point where she seems to just not know what to do with herself if she isn't talking. It's like this:
My husband: Okay, well, I've really got to get going now. Gotta get to the drug store before they close in ten minutes. (He has to come up with something like that, or he'll NEVER get away.)
MIL: Okay then, love. I won't keep you. I just wanted to see how everyone's doing. (Two hour phone call.) Sounds like you're all fine.
My husband: Yep.
MIL: And I'm glad the package arrived. Like I said, I couldn't decide whether to send you the blue one or the red one, so I sent both.
My husband: Yep. Thank you.
MIL: That's right. Like I said, you can always decide which one you want to keep, and it's always good to have a spare.
My husband: Yep, thanks a lot, mum. It's been great talking to you.
MIL: Oh, it's been great talking to you, too, love. And everyone's alright at your end?
My husband: Yep.
MIL: Smashing. Alright then. I just wanted to check and see that the package arrived okay, and that everyone is fit and well. And oh, did you know that they've made playgrounds illegal in Britain now because of all the pedophiles?
My husband: Gotta go, mum.
MIL: Oh, right! Well I won't keep you. Like I said, just a short phone call. Just to see that you got that package. And you did. I hope it's alright...."
AaaaaaaaaaaaaaaGGGGGGGHHHHH!!
Phew! Some people are just like that, though. You have to just say, "Bye." And walk away, or hang up the phone. Just don't be like me and say, "Geez, can you just stop talking!?" Apparently people don't like that. 