Listener question: self enquiry

Listener question: When you talk about the ‘dissolving’ of beliefs I still can’t get my head around it. I have thoughts like ‘I am not strong enough to cope with this lack of sleep’ is that a belief in itself or a thought coming from a deeper belief e.g. I am not resilient? 
When I question this belief my mind comes up with lots of evidence as to why it is true e.g. my buggered immune system and my tiredness (staying out of the story of these as much as possible) 
My mind seems to then hit a wall and I find myself tracing back to questioning the ‘I’ in the belief e.g. who is it that is not resilient? 

Perhaps I’m just not entirely sure what self enquiry actually is at the moment it seems to be creating shit storm confusion rather than a portal to what is true.