I get what you mean about the failure element. I also understand why you feel like that despite rationally knowing you shouldn't or aren't to blame. Being able to get pregnant, being able to carry a baby to term and being able to give birth naturally are all things we are pretty much brought up being told we should be able to do, I think. It's hard to let go of that. In your relating what happened, I was focused on how amazing it is that we can now give babies a chance when they are premature. It truly is amazing! It brought a tear to my eye.
My situation - he left to go back to his family (in another country) due to the breakdown and I am waiting on him to decide whether he will return. He will have to decide soon. That's where my username came from. I was talking to my mum about the situation today. She is protective of me and has gone off him a bit (she really liked him before this) because she sees the impact of his behaviour on me. Not that his behaviour is intentional (to affect me negatively), but a by-product of his breakdown and him trying to figure out where he goes from here is that it obviously impacts me.
I'm at the point where I feel as if what is meant to be will be. If he chooses not to come back then he really wasn't the right man for me. If he is he will want to return. Rationally I know that, but I don't always feel rational about it. I feel helpless and hopeless sometimes and very sad and a bit tearful and go through bouts of depressed feelings (especially if I'm hormonal).
I also feel like what is happening with him, as you said about your H, is likely temporary. How long temporary is, I don't know. I kind of think that if we do break up, he will regret it, as you have said before about your H. I don't say that about myself in a big headed way, but he said to me that he had not met anyone like me since he'd ended things with his long-term ex some years ago, despite dating/short term relationships and he has said that I have not put a foot wrong. So it does lie completely with him. If we have done nothing to cause it really, and it is them and their breakdowns about things, then we are stuck as we cannot fix it, can we? There is no role for us to work on anything with them. We are just bystanders really.
So with that being said, I feel I just have to take this time to concentrate on myself. I am building my life up without him and I want to get myself into a good position so that whatever happens - if I decide to be single, to date again or he comes back - I am in a good place.