P.W.
Your post really breaks my heart. Is it actual chemical depression? Have you tried any antidepressants? If your son's father is newly in the picture, is he any good at anything? He may not be helpful with the depression per say, but are he and your son bonding? If they did it would be really helpful for your son. Boys, esp. teens, really need fathers. What insurance plan do you have? There definitely are people who treat teenagers.
Lots of questions, and few answers, but teens with problems are who my heart really goes out to, and I'm really concerned about your son. Please let me know how it goes, and keep trying.