A few years ago I came across Byron Katie's Work and more recently direct awakening (no-self, liberation,nonduality,pathless path, advaita vedanta) material like that of Ramana Maharshi, Tony Parsons and those guys (usually people who talk about their "self-realization", the nature of thought, the futility of talking about these things, call out other speakers @.@ etc.):
Greg Goode's (I think) written overview for those with a philosophical streak: https://www.scienceandnonduality.com/article/nondualism-in-western-philosophy
And most importantly: https://youtu.be/VDeedQsTAsU