It's just something that is characteristic of females. I sort-of got the concept after reading Deborah Tannen's book You Just Don't Understand; Women and Men in Conversation.
The behavior has something to do with "building/maintaining a relationship" and what is so difficult to understand is that apparently what they talk about is almost irrelevant, as long as they're talking.
Men talk to exchange information and when that task is accomplished they stop talking. Women will never understand this.
That's why when a husband doesn't say anything to his wife for three hours she starts to think something's wrong with the relationship, when in fact nothing is wrong, it's just that he didn't have anything to say.
That's why it is important to listen to DW even when she's apparently just yakking for the sake of yakking, but what she's really doing in her mind is working on maintaining the relationship. So just nod your head and say "Yeah" once in a while and go on thinking about whatever else it was that you were thinking about.
Now, if DW doesn't say anything for three hours, I know there's a problem.
This stuff is really up there with trying to understand nuclear physics so it should be easy for you to get.