I have yet to read some of the more recent messages in this thread, hope that's okay.
It seems to me I'm sort of similar and sort of different, personally. I think for me, emotions, when they do come, tend to come naturally and automatically, and I don't decide on experiencing them (maybe expressing them, though1) consciously. However, I sometimes feel like emotions don't come to me as readily as they do for some other people. I don't seem to be as bothered by negative things happening, especially when they're the major types of things (death, loss of friendship, etc.) that it seems people typically feel the worst about. A notable exception to this is a romantic break-up. At the same time, I often get more bothered by little things, like when I get into a discussion with an anonymous person online who, from my point of view, acts in a very bigoted way, and won't listen to reason. And I think I'm more likely than other people to feel bad about very specific things such as not achieving as much as I want, academically.
Now, honestly, I don't think it's entirely ordinary to be this way with emotions, in the sense that I think it's somewhat away from the mean, if you will, looking at the whole experiencing-emotion thing as a kind of spectrum. But my talking about it as a spectrum already implies there would be some variation, and I think that's natural, so in that sense it's not necessarily abnormal, either. If you get to some extreme, you might be an outlier, and that might be kind of like being abnormal, but I couldn't say if that applied to you.
If it did, though, I still wouldn't hold it against you, nor do I think you yourself should. This may just be me personally, but I tend to think people should be judged, if at all, on their actions, not their thoughts or feelings. If you never feel bad for a person, but you still are nice and sympathetic toward them and help them out if they're in pain -- as in fact it sounds from your original post you tend to do -- then I think that's good, and I don't see why anybody would or should get down on you for that. Especially considering that to a large extent, you can't help the way you are, particularly concerning things like this. That might be the most important thing to keep in mind, for that small part of yourself that was worried about it rather than just interested in a more academic way.
I also think -- and I hope this is not going to be a controversial thing for me to say -- that on these boards, you are more likely to find a larger proportion of people similar to you in this sense than in the general population. Some people are more geared toward the rational than toward the emotional -- there's some link to autism here, although I'm not suggesting that's necessarily the case if you are anything like this2 -- and I think people who are generally a bit like that might be more likely to enjoy Dwarf Fortress. (There's a reason they say it's "the ultimate autism simulation" and similar such sentiments, although I think it often times is used as a kind of disparaging remark... which it doesn't need to be, I think.)
Anyway, I hope I made it sufficiently clear that I don't mean to make any presumptions about people, individually or as a group, and even if I did, I don't consider any of the characteristics I discussed as being anything negative, anyhow. But I don't.
1 - It seems in your original post you were referring mostly to deciding to express the emotion(s) rather than actually experience them, but it still sounded like that might be a part of it as well. I think that's a relevant distinction to make.
2 - In fact, I'm kind of the same way and I'm not autistic (I was tested), although I have some characteristics that point in that general direction.