I talked to the doctor a couple years ago. Remember, I am a bit older than most here so some of my problem is age related. It seems that since I drive so much, my eyes are used to almost constantly looking far away. Most drivers don't do this as much as I but I actually went to school to learn "How" to drive properly. I have Class A CDL's and as such tend to look as far in advance as is possible during driving.
I drive on average 16+ hours each trip. I drive on average 900-1,000 miles each day during each trip. As such, my eyes are accustomed to literally looking at the horizon a lot.
Now, at home my monitor is less than 18" from my face. I am not positive that that is the exact reason but it could be.
Common things that cause issues are the need to rapidly focus from close to far are killer nausea inducing stuff. Looking at this keyboard for instance, (yes, I am a looker, I cannot type without seeking the keys. Admittedly I am very fast at it, but I cannot do it without looking down) causes me serious issues with my eyes and as such, I will have to go away soon after posting this long reply.
But, anything that causes me to look near and not so near rapidly will cause me serious issues.
Worse, if its snowing when I drive I must pull over till the storm abates. The constant flakes coming at the wind shield will have me blowing chunks within half an hour.
Anyway, I already wear glasses for driving purposes. Up until my last eye exam I did not require them for anything else as my eye sight is still 20/20 otherwise. My glasses are simple clarifier's. There is almost no magnification noticeable within them.
/ rambling.