Fred Pohl once remarked; "The good news about writing as a career is that the income curve is asymptotic. The bad news is that it starts at zero." It wasn't till the early '90s that I started making enough money to actually live on and support my family—Lois McMaster Bujold, in an interview that appeared on Baen.com
I'm sharing this quote because it touches on the careers of two people in the topmost rank of my pantheon of admirable writers.
Frederik Pohl, in his memoir The Way the Future Was, recounted that he felt like a failure during the first year of his first marriage, but that certain things he wrote that year continued to earn money over the course of his lifetime, and that in retrospect he realized he'd spent his time more wisely then he knew.
Ms. Bujold informs us it was almost a decade before she could earn a comfortable living as a writer. Yet I can't think of another SF author in the last thirty years who has had a more enviable career than she has.
One thing they have in common is that neither of them gave up.
Food for thought, that.