Hi my name is Chris, and I'm a Guitar-Habit-O-holic Too!
I think the reason why most guitarists never improve is that we always play what we are comfortable with. It probably stems from a problem deeply rooted in procrastination. I'm sure deep within you, you have a bunch of licks or phrases within your head. Take those phrases out and transcribe them on your instrument.
Even if you've been doing the same exercises/patterns, it might be a good idea to mix them up ie. Use them with different intervals, scales, string skips, legato or whatever, or better yet use them as connecting phrases in your melodies.
I hope this helps, this has been a problem that I myself as a guitar player have been struggling for with the last couple of years. I think getting a new book, listening to a new player or whatever is good. But it's only going to take you THAT far in your quest to improve, actually getting there is really up to you
IT'S TIME TO BREAK OUT MAN!