I'm not quite sure what to say...

The way I read the letter... Was that your employer IS trying to be understanding about this:

> Just to follow up on our phone conversation, I'm sure things aren't easy for you right now and I am trying to understand that. I know you are making a good effort, based on your decision to stay through the end of the week.

BUT that they are really struggling not because you made 'a minor mistake', but because more generally:

> half or three-fourths of the time

there are errors (and concrete examples were provided).

I understand that you are having a hard time... (And I understand that you might not hear me when I say that). But then I also understand that as an employer one needs to have employees who do their job - or one needs to find another employee to do the job or to fix the mistakes of that first employee.

Maybe you need some time off? Or maybe... If your depression is fairly constant and you haven't had these issues with other employers then you might be better finding an alternative position?

It IS hard. Because on the one hand, we don't want people to stigmatize against those with mental illness (e.g., by not hiring them etc). But on the other hand, when we want special consessions, then one can understand why there is such stigma. I'm not quite sure what to say. But I AM sorry that you are having a hard time of it. Maybe... This job isn't for you.