I've been diagnosed at 60 and I'm trying to put the puzzle together. I tend to have a short fuse and I always felt so bad after.
As an example:
Tonight I'M playing poker on the net and I have a better hand that the other guy at the start. He beats me and took all my stack.

I get so upset, I curse, hit the table.. My wife looks at me and laughs and wonders why.

Anyone like me

I always feel bad immediately after I've yelled or snapped at somebody, even if it was justified.

Heh fuse.

Having a low tolerance for frustration is common with ADD.

Having said that, I've been known to lose it when I get delivered a bad beat from a donkey player ("But they were suited!") ;)

It can also be PTSD. Its not only for soldiers in war, its for all of us. Check out the ADD and Anxiety forum.

I noticed that when I was around one of my friends in high school that also has ADD, we got along well despite our short fuses or impulsive comments/actions. We would argue a lot or yell at each other but we would get over it fast. However other people would tend to get upset or hurt at which point i feel bad or embarrassed.