Realise the following things:
1. If you rage-quit on life, you're fucking up your family for life.
2. Now that rage-quitting is hopefully out of the question, you have a long life ahead of you.
3. things will not get better by waiting around. find a way to improve your situation, or turn your life more towards stuff that makes it worthwhile.
Anythign from getting good at a game, playing/watching through a series you wanted to play/see, doing sports, doing better at school, taking extra shifts at work to save up money. Basicly anything you can look at and feel like you've achieved something, be it a personal desire (like beating a game) or more common stuff, like gathering some savings.
Set goals like the ones mentioned above for yourself, something with a solid criteria for completion like "i've watched this now" "i've saved up the 5000 i wanted" "i've improved my grades" "i can now lift more/run further/got my new belt" "i finished my drawing/short story" "i managed to quit ciggarets"
Adding purpose, even if it's small or can be considered unimportant like gameing/watching stuff is always nice.
This is not meant to sound cold, but distancing yourself from your emotions, at least temprarily, untill there's room for more happy thoughts to be there as well, can be nice sometimes, and it can make it easier to "grind through" if the things that are bringing you down are things you have to go through for a period, like school, a period of overtime at work, passing time while unemployment etc.
if it's hard to be happy, beeing able to see that you're making progress in some other aspects of life can help keep up faith in that things will get better.
I got through some depressed times by grinding through at school and work, in order to not make my situation worse, and then getting high when i got home, but the last part is probably not considered good advice, especially if you're not sure you'll fell better by doing it, and know you have the discipline to not let it make your situation worse
Check out a therapist if you don't think it's something you can pull through on your own.
Obvious Disclaimer:
I'm no therapist, and all advice is based on personal experiance and is not a professional oppinion.