I love creating but I do the same thing and torture my physical health sometimes xD What drives me is that even in the most tedious processes or even the latest of hours is seeing something that I created to completion. I don't finish some art works, which always bothers me and they become something always in the back of my mind. To prevent that, I try to make sure as much of an episode done and then complete it even if it's late.
I've had a similar experience. I have neuropathy in my hands and feet, which means they are numb and tingly all the time because my nerves have been badly damaged. They're getting better slowly. Last year, my hands and feet were much worse, they were painful too, but what really made me depressed were having my hands pretty much useless because I couldn't do simple tasks like button my buttons by myself AND I couldn't do anything creative like draw or write. Creating is something that helps me so much in my healing process from all that I have been through. Before, I couldn't imagine my life without it, but I got a terrible taste of what that would be like and I felt miserable. I am sure I'd probably get used to different methods of creating, like with my mouth holding a stylus or pencil, but it'd be a long journey.
I love creating. It means the world to me and I believe it is worth it despite it's challenges because the challenges make me feel like I've made tiny accomplishments, even if didn't climb mt everest. I have made small accomplishments that make me feel happy. It's akin to the physical therapy I've gone through. The little accomplishments make you overjoyed. Watching my art grow makes me overjoyed, creating an idea for an episode, making a dialogue for that episode, completing a panel, completing an episode, getting that much closer to completing an entire comic to it's full completion is my personal Mt. Everest and I feel good about each step I make. I really love creating, even the pain and anguish makes me feel alive because nothing will be as bad as what I went through last year. I am well enough to create and that makes me feel like life is worth living that much more for me ^^