Sorry to hear you're having a hard time. I noticed your ds said he would like a sibling when he's older so it sounds like he's happy now.
I worry about Ds being an only child and this is why we're doing Ivf. But in the mean time we make sure he has lots of friends to play with so he is well socialized, busy going out to things do he is never lonely. We can't change the fact that we might not be able to have any more children but I know that we're giving it our best shot. And if we can't have any more from my eggs we will try donor. Have you thought about donor eggs? Apologies if I have already asked you about this.