No service when desperately needed

My son is suicidal and I called Tara Hospital to make an appointment for him to see a Psychologist as he had been a patient with them from the age of 6-18. Once he left school he decided to go off his medication and try and cope in the real world. He is now 22 and needs help urgently so when I called Tara to make the appointment they said that I must get a referral letter as he has gone from Childrens Clinic to OPD, but the Childrens clinic doctors cant do the referral because they hadn't seen him for 3 years. I then asked them how a stranger could give him a referral letter and not their own facility but they assured me that this was their procedure and I must either go to a clinic or doctor to get the letter. I finally conceded and took him to our GP who gave us a referral letter. I called OPD again to make the appointment and they said that I can't use a GP referral only a Psychiatrist's referral letter and refuse to make an appointment without this referral letter - what is the difference - my child needs help urgently and they are turning him away. It is National Mental Health month and I can't get help for my son. I am very upset and extremely disappointed.