If it would make you feel better to share it, then please do. But don't do anything you're uncomfortable with.
That's really cool! You do music? Vocals, instruments or both?
If they left you when you pushed them away then they weren't true friends. (at least from my experience) Any true friend feels physical pain when they see another friend in need. I know I do. I'd stop at nothing to help them if one of my friends was hurting. This may, however, only pertain to my situation.
I can say now with 100% certainty, a parent under no circumstance should call their child "worthless" or "useless". It sounds to me like you've grown up in (at least) a mildly abusive situation. I don't want to jump to conclusions though, so please correct me if I'm wrong. Whatever you do, don't take it to heart. Everyone, no matter what sexuality, gender, race, or religion is priceless.
About depression and anxiety, here are a few things that might ease your suffering. I know how hard it can be.
1. Try doing a power pose for 2 min every day in front of the mirror. This boosts self-confidence and just makes you feel a lot better about yourself in general.
2. If you love animals, try to be around them as much as possible. Seriously, those things are instant-stress relievers.
3. Try to do things that keep your head out of the past. For me, this includes art and talking to my friend, but for you it sounds like it could be music. <3
Of course, these are just some tips that helped me through my dark days, they unfortunately won't work on everybody.
It's alright to be unsure for now. The fact that you're aware of what you're doing tells me that deep down, you're an amazing person no matter what you may think. A person who truly doesn't deserve forgiveness wouldn't care what they've done wrong and they definitely wouldn't try to fix it.