Go with the Socratic Method and point it at yourself.
"Why am I filled with self-hatred."
"I'm filled with self-hatred because of X."
"Why because of X?"
"Because of Z."
"Why because of Z?"
So on and so forth. Eventually, you're going to arrive at an answer for something you can't change: who you are, what happened to you, the way things have played out. Once you've identified what you can't change, then you can start looking at what you CAN change. And nothing so useless as "be happier!!!111" But things like: I can change A, B and C in my life and it will net me something. Move away from a situation that is holding me back or making me unhappy. Utilizing the time I have to do something that feels meaningful, whether it "actually is" or not. Draw for the sake of drawing, not because you're trying to improve or create something someone else values, but simply because it's a compulsion that fulfilling will bring you joy.
Alas, for some people, the world will never be as hard on them as they are on themselves. Learn to recognize when you're not being fair to yourself. Learn to distinguish between justified self-hatred (that thing that makes you police yourself) and unjustified self-hatred (wallowing in the past or refusing to accept who you are, whether that's physically, emotionally or mentally and continuing to beat yourself up about it.)
Imagine....and this might sound like a trite example or a deflection but....imagine being someone with an obvious cleft pallet. Someone with an physical deformity they can't change, can't escape, can't hide and just have to deal with their entire life. Cerebal palsy. Multiple sclerosis. Being in a wheel chair. How much personal strength must it take to look in the mirror every day and go "I can live with this." Or pick any deformity, abnormality or defect. This isn't to downplay your feelings and perceptions but to provide context.
For me that always makes me feel better about my situation. Makes me realize, I'm actually dealing with what most people deal with, but because it's me and my whole world, of course it seems like an insurmountable problem at the time.
But yeah. Stop beating yourself up. Give yourself permission to suck, and then start thinking about what you really want out of life and what it will take to get there. Think about work you'd like to do that seems reachable, that you won't hate, that will provide you with what you want. I'm not going to do the whole "chase your dreams" thing. That's by definition for dreamers and people with a high tolerance for risk and failure. Instead, be honest with yourself about what you absolutely need, what you want and what's reachable.