I think a lot of creative people (writers, artists, musicians) struggle with "burnout" or "writer's block." I know I have. As I've gotten a little older, gotten to know myself a little better, I've found some ways to avoid these things.
The first is knowing when to rest, to relax. When I was a younger man, I would constantly push myself to always be creating. I would give myself a schedule like, I'm going to write from 5-7pm, or I'm going to paint for one hour this morning. What I discovered is that I cannot "force" inspiration. If I'm tired or frustrated, then writing or painting is going to feel like work (i.e. not fun). So I have learned not to schedule creativity, but to trust that the impulse will come, if my heart and mind are willing to ride that wave. One way to allow that inspiration to come is to allow myself to rest. I take naps and feel no guilt. I quiet my mind and my heart in preparation for the ideas and the drive to create. And because I'm ready, it comes.
The second important thing I've learned, to avoid burnout, is to constantly be searching for new things: new music, new books, new films, new art. "New," of course, doesn't have to mean recent. It could be a ska song from 1965, or an obscure Italian film. What I am hungry for is "new to me." There is a fathomless ocean of inspiration out there and I try every day to take a little dip. The books and music and films are a wellspring of inspiration.
The third thing is self-awareness, knowing your internal rhythms and being gentle with yourself. If you push yourself too hard, all the time, you will burnout. This takes time and trial and error. But you if practice this self-awareness, you will learn, again, when to rest, and when to write like hell.
The last thing is to disconnect your internet service and destroy your television. The internet and television can easily become life-sucking distractions. I do not have home internet or a working television. When I am home, I can read or write, eat and sleep, be with friends. When I need the internet, I can go to a variety of locations (the library, the local coffee shop). Cutting out these frivolous distractions has been immensely important to me.
So those things (rest, new things, self-awareness, disconnecting the net, destroying television) are what keep me creative, and happy, and sane. With quiet practice, reflection, and inspiration, you can cultivate a rich creative life. Your creativity can become an everyday part of your life, something you just do, like eating and sleeping. This is possible, and it is good.