Why can't cisgendered people understand us?

[auntysarah.livejournal.com]

Something I've noticed since I started my transition. Lots of people have said that they respect and support me (yay!), but they don't come close to understanding.

Initially, I thought that it should be easy to explain, just by doing the following thought experiment:

Imagine that tomorrow morning you wake up in the body of the opposite sex. You have all the secondary sex characteristics of that sex, the voice, physical strength, etc. etc.. Everyone treats you as though you are that sex, and if you continue with the mannerisms and behaviour associated with your original sex, you will be ridiculed or even attacked for it.

However, you feel exactly the same as you do now. All that's different is your body, and the way people react to you.

Now granted, someone performing this thought experiment won't have the "benefit" of our experience of years and years pretending (probably badly) to fit in with their physical sex, but I still think it should give most cisgendered people a reasonable idea of how we feel.

But almost to a person, they simply don't get it, at all. It seems that they can't perform the above thought experiment.

Someone's missing something, and I suspect it's partially me and partially the people I've tried to explain it to.

Any thoughts?