i really understand the work issue and how hard it can be to push at your job til you can't do it any better. i had to quit my nursing profession of 35 yrs in '05 after at least a yr of pushing til i thought my job was killing me. my BP was thru the roof from the physical effort of it all. it was just too physically demanding. and then there was the cognitive. that's when i really knew i had to leave.

try to look at each problem and see if you can find an answer to it. you will
probably have to do this with your dr.

checking the B vits and vit D is very important. can you take something for the fatigue? and there may even be something that might help your cognition.
is there anything that would help you that you could change at your job?
if your employer knows you have MS there might be some reasonable accommodation they could grant you to help. that's the law under the americans with disabilities act.

please let us know how you are.