I understand how therapy can be tough. I once told my therapist that I felt like melted cheese after a particularly intense session.
As for your question about walking away from your family--yes, you absolutely can, if that is what's best for you. But, you mentioned being a perfectionist, which I can relate to as well. Sometimes perfectionism manifests as black/white, either/or thinking. It sounds like you are somewhat enmeshed with your family. So, while walking away completely is an option, it's not the only option. You can create some space in the relationship and set some boundaries as well.
You don't have to figure everything out at once. Just do the next right thing for you and your little one. Keep doing that, and the rest will fall into place.
L