I too am not great with heights, strangely I am fine when inside a building (no doubt from having worked for a couple of years on the 36th floor with full height windows) and am ok on ladders (as long as 'someone' isn't fussing around the bottom telling me to be careful) but put me in the open three floors up and I am not great. Like you, I can't watch anyone on tv doing anything at a great height!Its more a fear of falling. I cant even watch heights on telly, even get pains shooting down my spine at its worse. But can work on roofs and high scaffolds!!
Bizarrely, this is one of my favourite pictures...