Charlies "flashbacks": What does he describe? Why or how is it important?

"......this morning just after I woke up, I was laying in bed with my eyes open. It was like a big hole opened up in the walls of my mind and I can just walk through. I think its far back... a long time ago when I first started working at Donner's Bakery. I see the street where the bakery is. Fuzzy at first and then it gets patchy with some things so real they are right here now in front of me, and other things stay blurred, and I'm not sure..."

He goes onto memories that come in small snapshots..... these memories are bad memories.