I'm looking for a word that describes knowing something, but not acting on it. For example:
I know eating healthy food is good for me, but I don't do it. I'm guilty of ____________.
I'd suggest inaction
Inaction [MASS NOUN] Lack of action where some is expected or appropriate (ODO)
It's simple and it implies that you should do something, i.e. eat the damn vegetables.
This may be a case of procrastination.
(Your example implies that you are somehow regretting that you are not able to put your knowledge into action; in that sense you may be indefinitely delaying it).
The action of delaying or postponing something: your first tip is to avoid procrastination
Indecision and inaction can lead to bigger problems in business so avoid procrastination and delay.
As if this delay was not enough it was further compounded by procrastination in implementing the action recommended.
Maybe it'll help a few aspiring writers realize they're not alone in their procrastinations.
dithering, delaying tactics, dilatoriness, stalling, temporizing, hesitation, vacillation;
British humming and hawing; informal dilly-dallying, shilly-shallying
US informal kicking the can down the road
I would go with apathy.
Simple Definition of APATHY
: the feeling of not having much emotion or interest : an apathetic state
Alternatively, indifference would also work.
Simple Definition of INDIFFERENCE
: lack of interest in or concern about something : an indifferent attitude or feeling http://www.merriam-webster.com/dictionary/indifference