Can you see the difference between this:
'I punish myself due to toxic shame, question myself even when I know I am right and make a lot of bad decisions but just feel too trapped down a well to do anything about it because I don't trust or love myself'
and what you've just said about how you'd treat a child? With love and understanding, and sensitivity to their feelings and a desire to not perpetuate their fear/discomfort?
If you can see the difference between those two things, you've got the solution to your problem. Nobody can change how you see and treat yourself, except you. You are an adult. You are responsible. You have a child to take care of, and if you punish, shame, and question her, even when you know she's right, if you don't trust her or love her, then it makes sense that she will feel trapped down a well.
When she speaks/shouts/tantrums, listen to her. She will continue to be upset, like any of us would be, if she isn't heard. That's what happened to her in her early years; her needs were dismissed. And now you perpetuate this. Indulge her. What does she need? What does she cry for? Give her everything. If she needs to scream, go stand on a hill and scream. If she needs to cry, cry. If she needs to hide under a rock, spend as much time as you humanly can under a rock. Indulge her. Once she feels heard, she will stop freaking out, stop feeling trapped down a well. She will start to speak quietly, and say things like 'I don't like this situation, I want to go home', and 'I think this person might be being mean to me, I'd like to go somewhere else' If you continue to listen to her, that will be your self respect installed into you, and you won't look back.
Acting out is a healthy response to unhealthy circumstances, you do realise that, don't you? If you were unhealthy in your mind, you'd just have accepted all that stuff from your childhood without a blink. The fact that you're responding the way you are shows that you have boundaries, and you know they've been crossed. You are healthy, and continuing with the healthy responses you learned as a child. You just need to adapt, which is good news, because all of us, as humans, are brilliant at adapting.
Use your feelings as a signpost, rather than something to be shushed. You are silencing the map and then feeling lost. Listen to the guide inside you.