Hey nerdmmb! I had the same problems as you around last year-ish but I managed to overcome it with a few things!
So I changed from studying in a room and moved outside to my living room. Sure it's strange studying in the living room but it's an open space area and the desk I got to use was bigger than before too (sometimes my table is a bit messy so I take my work and study on the kitchen table and I'm pretty motivated there LOL)
I also stick my goals for the year in my room and wherever I'm studying so I can see it ad be reminded why I am studying! It's a long journey and being reminded of it certainly helps (for me).
As for procrastination... well I've substituted it for other stuff so if I see myself slacking off then I get up, go get a drink of water or a snack and come back. Sometimes I go for a run (whether it be in the afternoon or at midnight [highway runs are pretty good if you're up for it LOL]) but yeah whenever I feel like I'm procrastinating I just get off my chair really.
Oh and I deleted my social networking sites off my mobile devices so if a notification came up on FB then I wouldn't be inclined to view it (sure I could turn off the alerts and stuff but I feel more secure deleting it I guess...)
But yeah procrastination is fine but just don't do it too often I guess!
I'm getting the impression that AN, despite its awesomeness, is somewhat of a distraction? Well, it happens to me occasionally 
You can customise your profile to exclude certain boards when you're viewing the forum I believe (if that helps).