That Tolle quote about suffering is very true.
Uber, I am an artist of sorts too. And I have long shed the belief that my creation has come from a painful place. I believe that one can create their best work when in a peaceful/joyful state of mind. Negative emotion put in art resonates with people on their ego level: it triggers their own pain bodies and they feel emotionally moved and, due to not knowing better, think "oh, this is real art" when in fact it is just exploiting and manipulation of ego/suffering. To the contrary, when a joyful/peaceful/enlightened emotion is put in art, it resonates with people on the level of soul. And that is art in it's purest form.
I do graphic design and I think that it is partly because of my profession that I am able to relate to the ideas of Power of Now and LoA with such ease: I have recently observed that when I work, I enter Now. When I do some really nice pieces, there is nothing else on my mind, just the current moment and improving the current moment and making it perfect. It has nothing to do with suffering, but everything to do with being fully present. And the more present I feel, the better my works are.
And on a slightly different note, I too have been in this situation where I know what is good for me, but keep harming myself. That is what was on my mind when I wrote previously in this thread "but if you will need this lesson, you will choose to have it". Your choices are not essentially right or wrong. They are the ones that you need to make to experience to learn whatever it is you are learning now.
I send you all my love and support in your journey.