I think some of this comes from our gaming generation, with each new game that comes out we expect more from it than the last. I've set the game down a few times myself which is nice to be able to just log back in once I feel like playing again and pick up right where I left off. This latest update offers many new things to capture my attention for a long time to come. The loot system makes it easier to gear your current char than prior.
If you own it you should join the clan and even if you barely play you could join some friends every now and then, and who knows maybe a spark of fun might start again.