mental tools to help me play longer hours

[PunchyPlay]

When I play poker I try to have the mindset that for every hour I play I make xxx$ and I try to ignore any swings and just put in the hours. My problem is that when I'm winning or on a very good run I always let myself have more breaks or time off etc. This becomes a real problem at higher limits because often times you can make your monthly expenses x 3 in 10 hours. You end up only putting in hours when you are running bad and combine that with being rusty from not playing much makes for a bad combo. At lower limits I consistently did > 130 hours a month, at higher limits I am consistently < 100 hours a month.

I can only seem to put in lots of hours at higher limits when things are going average or bad. Does anyone else experience this and know of something I can do to help myself just put in the hours? I know it all boils down to discipline but I guess my discipline sucks in this regard because I always slack it up. What does some high stakes pro think about when they put in 160 hours in a month and make 80k? Why don't they stop at 50k and just take the year off? It must be an issue of setting higher goals for themselves or something. I guess my only goal is to get a house and be able to live off poker part time very comfortably which is hard to do at 1/2 and 2/4.

Tips on improving discipline in general might be helpful too.

Thanks for any advice