changing custodial parent

I am female trying to change a court order of custody, my son was placed in permanant custody with his father at the time of divorce. I suffered a emotional breakdown requiring medication that clouded my judgement, we both had no whwere to live at the time . since this time 5 years i have been employed at the same job have turned my life around completley. My son has always wanted to live with me but his father has contested. My son is now 16 years old his father is in welfare which is where my support goes I pay 407.00 per month which is garnished from my income, Oh yes I live in the State of Washington, I buy all fo my sons clothing ,hygiene needs , haircuts, school suplies everything he needs that I can afford. His father uses none of the money on my sons needs I often take him to school when he misses his bus because his dad has no gas.My son is capable of saying what he wants, but who do we tell The state of Wash. rarely changes court orders of custody. My son is with me almost all of the time. and I feel I should not have to pay for his fathers living expenses, which I am. please help me find a way to have my sons voice heard. Thank you - Is this your question? Add additional information