Depression during studies: how can I recover ?

I'm 18 this year. And started getting depressed at the end of year 10/start of year 11. I just kept crashing and crashing, couldnt concentrate at school, no interest at all.

I was going for a final result (OP where i come from - Aust) but i couldnt cope and didnt get anything.

Its 5 months into the year after graduation and I live at home and only leave to go to psychologist/psychiatrist appointments. I hate not knowing what I can do and I dont even understand what is happening. I feel like it would be so easy to 'snap out of it' and just carry on, but I cant even manage that. I havent had any contact with any of my friends, and wonder if they even remember who I am. Questioning lifes purpose and my own.

I dont even know what i'm asking right now, its just too confusing.

If anyone has been through this and seen it through please tell me what you did to deal with it and get passed it all.

thanks. Mark