Some of this is pretty specifically tailored to myself, because that's why I wrote this, so I can read it and remind myself that these things are all true for me, and hopefully after I read them enough, I'll begin to believe them at some point.
#1 Just because you failed, that doesn't mean you're a failure. Even if you failed at 10 things. You're still not a failure. Even if you failed at 20 things. You're still not a failure. Even if you think you've failed at everything. You haven't. You have a place to live and you have food. That's two things you've succeeded at, and there are plenty more.
#2 Worrying isn't worth it. It's just not. Worrying sucks. It sucks away your joy of living. And worrying about things doesn't help.
#3 Sometimes it's okay to spend money on things you don't need. Don't go buying a Nikon or anything, but a manicure would be okay to get. Even just once. And it's on your bucket list, so do it.
#4 Schedule time for yourself. Quit making amorphous plans to sometime spend the day shopping for painting supplies and selling CDs (Yes, I still have CDs.) and going to thrift stores and just do it already. And check out that new crepe restaurant on The Ave while you're at it.
#5 Stop feeling guilty. This goes with the above part. Know yourself and your issues and that getting a real person job probably isn't going to happen for you right now. Because of reasons. Mostly social anxiety. And don't feel so guilty about it. Just use your time wisely. Make jewelry when you feel like it, and don't cut yourself down so much when you don't. See if you can volunteer at the library one or two days a week and get used to being around people and gain work experience at the same time. Boom: two birds, one stone.
#6 "Can't" isn't a word so stop saying it. Give yourself the opportunity to succeed and don't worry if you fail. (See #1 and #2 above.)