I flout my GTD, all the time.

I'm currently having real difficulties following my GTD routine and because of this i'm letting things slip. I've recently been getting home from work and not doing anything at all, flouting my next actions and deciding what to do there and then (which usually involves playing games or watching TV).

Today i'm sat in work and i don't even have a copy of my NA's or my moleskine to hand, i've left them abandoned at home in my bag.

I love GTD but i'm having great difficulty applying myself to it. Has anyone got any suggestions which may help me stick to my routine?