Whatever you choose to do, make sure you enjoy it. I know this sounds like an obvious statement, but I've known several people who never followed their original dream career path because it didn't seem feasible at the time. The result was their being stuck in jobs they hated, which drained all happiness and energy from all other aspects of their lives.
If you wish to focus on your writing, would you consider working, for example, a retail job to pay the bills until you can make a living off your writing? You know, a suffer-for-your-art kind of thing.
If you don't pursue your writing you may regret not doing so for the rest of your life, so I reckon it's certainly worth a shot.