You have your degree, you had your six month internship, you received your certificate of accreditation...and you simply cannot find a job in a market where you want to live. Mom and Dad's basement is starting to not look so bad.
You get part-time work with a psychotherapist who isn't convinced music therapy is a 'real" sort of therapy anyway, and she calls you about once a month to work with a patient who isn't responding to anything else.
You have a decent job working at a hospital where your skills are recognized and your success rate relatively high. You work in tandem with other types of therapists (physical, occupational, etc.) to ensure your clients are getting the care they need.
You've started your own practice because of the success you found at the previous hospital you worked at. You've incorporated what you learned at school and during your internship with what you learned from real-life experience to create a method that is well-respected by clients and peers alike. Consequently, you have no shortage of clients.
You have your own practice, your success rate is through is the roof, and there's a long waiting list of clients trying to see you. You're well-known in your field, you publish at least one book a year, and you're constantly being invited—for a high fee, of course—to give lectures and workshops all over the world.