The other comments here have mainly added what I had wanted to stay. Particularly what ironlake said about climbing to another level fo Maslow's hierarchy of needs. So I will approach this question from a different point of view.
On the aspect of motivation: It seems like the reasons you had for pushing were externally focused (going to get into the big leagues). But what motivates you internally? Why chase those habits? Those habits existed to serve you at a different point in your life. Ask yourself why you feel the need to chase the same you as back then. You can sustain a roaring fire for only a short term, perhaps you need to look for habits that can sustain embers that burn for much longer.
The other thing I want to state is that complacency and ungratefulness are not feelings. They are thoughts. Perhaps you are feeling insecure (I am no longer improving my skills) or feeling bored (I have nothing more to learn here). Note that the phrases in the parentheses are thoughts and not feelings. It's all too common for us to substitute feeling when we really mean thinking. Similarly,we fool ourselves into thinking that our rational thought precedes our feelings; it does not. Your cerebral cortex activates after your Limbic. You feel things first, and then your cerebral cortex uses your past experiences to attempt to provide context (loosely speaking).
So I'd really ask you, why those feelings are and how you've processed them? Often if we're externally focused, we dull our interospective awareness.
The buzzwordy solution to this is do mindfulness meditation! Honestly though, you don't need to meditate. Just do things that you're able to practice being mindful.