Unraveling

[Quixilated]

Hi Starlight, you have a lovely poem here.  I enjoyed the images you used to capture the chaos of a fractured mind, and the narrator's inability to comprehend that what has happened has happened.  I especially love the mice of mind scurrying so frantically that the narrator can't even think of a name.  I have a few suggestions below that you are welcome to consider if it helps.  

--Quix

A simple word shatters at the thought   any word or a specific word? for some reason I got hung up on this.
of a million of lost connections   using million twice in a row ... maybe find a different way to say one of them.
A million tightly twisted knots unravel some of your lines are capitalized at the beginning and some are not. Lowercase "a" here.
 
The unintelligible mice of mind I love this image.  Alternate phrasing idea, "mind-mice" but I like what you have too
Skitter scamper squeak  I don't think you need all three words, maybe pick one and merge it with the following line.
in overpowering commotion,
Drowning out your own name lowercase d
 
Waiting for the day when numbers
order the way they're ordered to  "order" twice in the same line, consider replacing the second with "meant" or its equivalent
Three six five, just letters,  symbols? lowercase t
The meaning as fragile lowercase t
As the fallibility of the mind lowercase a
That promised to hold on to it lowercase a