I used to find the chapter in "High Intensity Training the Mike Mentzer Way" titled "How to develop a Seige Mentality" really helpful and inspiring. i also liked to watch Dorian's training vid for a boost, but nowadays it all comes from myself.
You just have to mentally train yourself to put all the other shit aside for an hour and get out there and get it done. It isnt always easy and i recently had a large dose of the same shit you're talking about and yup, it fucked my training, but you just have to get back on track, re-focus your mind on what you want to achieve and then do it.
or you could try internet porn