Perhaps this is your sign that you need help then eh? The only way things will get better is if you put the effort in dude. Your mum was actively trying to help yet you spent 2 hours shoving all of that back into her face. Apologies only go so far; actions speak louder than words.

You want to apologize, you need to show that you're willing to move forward, even if it's hard. I'm 34 with chronic depression since i was 11, but I do my absolute best to keep it from spreading to others. I won't deny that I should get medicated, but that's on me to do as an adult. Your mum is trying to be the adult and get you help. But ultimately, it's much like AA or NA or whatever Anonymous Help groups there are... you have to take the step to acknowledge things, and then take the step to move forward.

Even if you want to take a nihilistic approach to life and saying that life in itself has no meaning, you can always give yourself and your life meaning. What meaning do you want your life to have? Only you can decide. But if people are trying to help you get into a better headspace, try hearing them out sincerely.