The myth of the tortured artist needs to die.
Writers are lying to themselves when they say their pain is necessary for inspiration, that peace and contentedness create fallow and dull periods of work. It's the whole "You can only write when you're single... log off Twitter once you become a wife," thing.
They believe that happiness is dullness. But that's only because they've trained themselves to use pain as inspirational fuel, and think they need it because the sharpness of it feels important.
It's a convenient excuse to self sabotage. It's a way to sustain the loop of self aggrandizing suffering, and never truly change.
If a writer never breaks this cycle, they might never realize that the problem with pain as fuel is that it's limiting. Pain is navel gazing. It tells you that it's the only important thing in the world, and ignores the entire broadband of human experience and emotion.
It forces a person to look inward and ignore the rest of the world, and as a result everything they write to justify pain will always make them a little less of a writer than you could be.
It's possible to write about pain and suffering without being stuck in it. Once you're not flailing in pain, you can actually see it with much more complexity and depth. Once you expand your happiness and curiosity and warmth and love, your knowledge of other emotions will expand too.