S Tax

I've been listening to Porcupine Tree's She's moved on whole week and have been pondering on not completely unrelated note; how do people get stuck? On idea? On a person? On a (disfunctional) relationship? I often see things like that happening. I do acknowledge appearances of those situations. I could dismantle such a situation down to its possible components and make it look plausible... but I still feel that I do not understand how people get stuck and justify that situation to themselves. I mean; the only permanent thing in the world is change and that is only natural. We can all aspire to and succed in making this change customized, user-friendlier and more palatable. So why do we get stuck?