How hard can it be to find a new dress?

When it comes to me, apparently very hard. I'm reading at a friend's wedding next month, so I've been looking for a new dress. I've been looking on the internet because I find I pretty much hate shopping the older I get. But guess what? It's not any easier on the internet. I've bookmarked a couple of things, but I just can't commit. You'd think with the endless choices available on the internet, it would be relatively easy, but my main problem is that I just can't find a style I'm sold on. I'd like a dress that's modest, yet not a freaking nun's habit. Incredibly, those dresses don't seem to exist. It seems the only dresses being made nowadays are strapless or sleeveless or form-fitting or super-short. None of those things work for me.

These are the four front-runners, but I don't know which one to pick. I think it's really between the third and fourth. I just have to pick one and order it.