I'm so sorry for your loss, what a shock it must have been. My waters broke unexpectedly too, at just over 19 weeks but my babies lived for a further 6 days before my body decided to kick them out. It gave me time at least to come to terms with some of what was happening, although I refused to lose hope until it actually happened.
It must have been so shocking for you to go through the whole thing so quickly and alone, I'm so sorry you had to endure that. Don't worry about your reaction, you were in shock, it's perfectly normal.
I'm sorry also at your OH's behaviour at Christmas, I'm glad you came out with your story, even if it was abridged a bit, Many people don't want to say anything until you do, they are so afraid of causing upset, espacially if they are very polite types - which it sounds like your DH's family are? Men do grieve differently to us and can't possibly have the same connection. The fact he didn't see him can make it harder to connect too - men are quite visual creatures.
I hope you can let us support you as much as we can, I've found great support here - it really helps to talk to those who truly understand, which only those of us who have unfortunately been through this can.
Much love,
Nikki xxx