Have you tried to overcome them?
I'm terrified of heights, I cannot stand on a chair without shaking.
I acquired a fear of heights out of the clear blue sky one day. I spent quite a long time trying to figure out what brought that on. My best guess is that it is due to some particular incidents I experience in the military. Unfortunately, that fear came on me at a very bad time. I actually froze in place. That sucked.
I have since found that old-fashioned immersion therapy has done wonders to mitigate this problem considerably.
The standing on the chair thing was true for me, too, for a time. Especially when doing things which required me to look up, like changing a light bulb.
Looking up was more likely to induce uncontrollable shakes than looking down.
I once had to have a Ferris wheel operator stop the ride and let me off. That was embarrassing. And weird, since I rode Ferris wheels a million times when I was a kid.
Through regular practice of forcing myself to do things which require ladders or whatnot, I have nearly eliminated my fear and am almost back to normal. I can climb up on my roof and stuff now.
Another useful immersion technique I found helpful was to go to a shopping mall and go up to the second or third floor and go to the "sidewalk" railing and look down to the first floor for a while. The trick is to make your body relax when that is the last thing it wants to do.
I took a hot air balloon ride this past fall. When the balloon launched, I crouched on the floor of the basket. I thought I was ready, but it caught me by surprise.
The balloonist said that was the first time he saw someone freak out in the 16 years he has been ballooning.
But within a couple minutes, I was able to stand. And within ten minutes I was enjoying myself thoroughly, and was able to look over the side with no qualms whatsoever.
A great day. I highly recommend ballooning to everyone.
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