How do I tell my parents that I'm depressed and need help?

I'm depressed. I have been for years. I hide it from everyone because I'm scared of the reactions I'll get. Last time I tried telling my parents, it was a huge argument about me being too young to be depressed (I'm a legal adult), calling me ungrateful, and telling me that if I can't handle things now, it's only going to get worse in the future (which is turning out to be true). It's exhausting pretending to be okay, and I don't know how much longer I can try. I'm just really tired, and sadly, I can't afford the help I need on my own.