Take this with a grain of salt as I'm a newer fella.
Habits, like Mr. Ross said, habits are there to keep you drawing when all you want is to sleep or when you feel like you don't have time. Habits help a ton and they work best when you start incredibly small and consistent.
Also, when I get negative feedback or feel as though I've hit a plateau, I try and remind myself why I do art in the first place. For me, there are many facets to that answer and those many facets keep me going. So it might help to ask yourself why you do art, why you started art, what you love about art.
I've also found that keeping general track of my time spent doing art helps me feel better when I have a slow week. It's a nice reminder that my slower weeks are still better than the weeks when I was still ramping up my habits.
Make sure to phrase it to yourself positively as "then I'll get to draw" or "now I can draw!" instead of "now I have to draw."
I hope this helps a lil, I'm not sure I've done the absolute best at getting this structure of mine across.