I am so sorry for your situation it sounds incredibly difficult and I really sense your frustration.
Firstly are you receiving treatment for your depression, not just medication but also some form of talk therapy such as CBT?
I understand what it's like to live with someone who just does not understand what you are going through and who chips away at you. It's very difficult especially when you feel you're just at your wits end. I really truly get it as that's where I am. So my advice is try to at least talk to the person and explain that you understand their intentions are probably good but that their comments are making you feel worse.
If they refuse to change, then all you can do really is try to surround yourself with positive people or positive messages that will encourage you.
Would it be possible for you to get and volunteer your time until you find a paid position? That would be something positive that you can do with your time, and would get you away from the negativity at home.
Keep praying, keep studying, cry out to God and tell him all your woes. He is there, He is listening and he cares even if it doesn't feel too much like that right now.
Don't give up, this is just a rough phase in your life. God has better things planned for you.
Praying for you.