system
A chat on 4chan
human
Goddard actually covers some of this. I don't know specifically which texts to read, but I think one of the ones in the OP did, and if not, I would check the realneville archive in the OP and at least read lesson 4.

Short answer is yes, because your world is a reflection of your subconscious thoughts. However, this subject in particular will take practices people in this thread call 'revisioning' (don't accept past events, reimagine happier memories) and 'mental diet' (immediately quash out negative thoughts). Remember that everything in your life stems from your subconscious, and so your pain and poor impression of yourself will keep creeping up on you to reaffirm how you feel about yourself through others, so you need to not accept such ideas.

You probably realize that this isn't really the Law of Attraction thread, but instead the Law of Assumption thread, but you might actually get value from seeing content about Law of Attraction, because those guys are all about 'always be positive! :)' and stuff like that.
gpt
Thank you for the recommendations/advice anon!