I believe I've mentioned before that I have a really good imagination, good enough that I can see thousands of different possibilities in a situation equally easy, and as such can't really tell which of them is more/less likely, except by culling those which are a bit fantastical.
I unfortunately get a similar problem with my emotions. If, for example, you present me with a stimuli that would generally cause disgust, I would find it just as easy to display that emotion as I would to display no emotion at all. Or to show over-the-top happiness or something. It's not even something I have to put an effort in to or try to do, just something I have to choose to do.
Thing is, then - how on earth do I know what my real response is to it? If any response I give is a subject to choice? I mean, sure, this isn't always the case, and it's not always a problem. But I know there's a lot of situations where I know that I'm displaying that emotion simply through choice, and I could just as easily do a different one.
I suppose the logical thing seems to be to surprise me with something, and then hopefully the "real" emotion will be the immediate reaction (that is, apart from surprise). Don't know how well that would work, not something I can say I've really tried.
But I guess it's just really disconcerting and annoying - wondering if many of the strong feelings I have about various things are simply a result of choice, and not the feelings that would have arisen had they not been chosen, as such. Though perhaps then I would simply be vacuous. I don't know.