Facebook is very interesting from many different angles.
One angle is that it is a simple website, using no new technology that wasn’t around beforehand. As a web developer I look at Facebook with a curious eye as to why certain features are implemented, and I sympathize when they get backlash from users who don’t like the changes they make.
Another angle is that Facebook is simply the most prominent manifestation of the social Internet we’ve seen so far. It is now when people have iPhones and other portable internet devices, where wifi is common, and simply when other people participate, that allows and spurs the individual to communicate. In this, Facebook is not an object, it’s a platform. You wouldn’t blame your cellphone for delivering bad news, and this is similar. However instead of the cellphone being a one-to-one, sometimes people use Facebook to share it to many instead of just one. This has advantages (I like seeing what other people comment about on photos, for instance, also saves the person showing their photos each time they go to a person’s house), and disadvantages (visibility settings aren’t nearly as easy or explicit as they need to be, but also some people simply don’t have a brain-to-keyboard filter and post inappropriate things). The point here is that it is not Facebook itself that is the item of deire, it’s the fact that Facebook allows you to participate in such discussions and interactions and sharing, this is why people are “obsessed with” Facebook or “take it so seriously”.
It doesn’t have to mean anything. Facebook is certainly not a critical part in my life, and my group of friends do not post their breakups etc all the time so I would suggest that your data points may not be as diverse as they could be. Remember, Facebook doesn’t really tell you what to do with it. It’s the person’s desire and choice whether to add every single person they know, or whether to not add an aunt they don’t particularly like (as I have in one case). It’s a new social tool and the rules and usage hasn’t really been established. Heck, even with cell phones the usage hasn’t been established (using in the bathroom? really?) and they’ve been around since the 80s.