Saurus is much more blunt than I am, which is often a good thing, but I agree with the above. It's hard as hell but it's so important for you to stand up for yourself and say "I AM important", especially if everything and everyone around you is saying otherwise. That is so much easier said than done, I get it... I've been dealing with this for 14 years and have only JUST started standing up for myself and believing myself "worthy." Sometimes it can even just start out as hollow words or thoughts. You can say "I am worthwhile" and not believe it, but even just saying it is a solid first step. The more and more you say it, the more that belief grows in you until you realize it's true.
Don't get me wrong, it's not like positive thinking is your cure-all for depression. It's not by a long shot. But you can't start working toward managing depression until you understand that you're WORTH fighting for, you know? If you don't believe that, why would you bother fighting to help yourself? I promise, Jazzy, you ARE worthwhile. You are a genuinely good person and I hope that if you start telling yourself that, you'll start to see it, too. <3 Don't apologize for yourself. You are worth being heard.