Someone not long ago suggested that I was greedy for wanting more, after chemo (long story) I was not supposed to have kids at all, and have 2 lovely boys and am about 11 weeks along again. Apparently I should be happy with what I have, not always wanting more! Of course it is not greedy, I came to the conclusion that the person who said that to me regrets not having more themselves and are externalising onto others, she had the token pair, girl and boy and that is what everyone should have..... which is her problem really. But what I mean to say is that you are not greedy, you obviously love kids and being a mum, I do too, and am so greedy that I not only want the one I am having now, but hopefully 2 more after that!
About the wallking on eggshells around you, there probably isn't much you can do about that, often people don't deal with other's grief (or perceived grief) well, and I am sure that the holding off telling you was well meant, they probably didn't want to rub your nose in it. That is what I have found, many of my really good friends couldn't cope with my diagnosis 8 years ago, and just disappeared, and when I lost a baby at 6 weeks people would look away and talk quietly which annoyed me, of course I was sad, but ok, you can't change the way that they are, just look after you!
I am not sure on the D & C, I guess as it clears you out you could try again straight away, one of the more knowledgeable people on here should know, there might not be rules, just when you want to!
Kate