Ellaine...I don't know what to say. I originally wanted to have all my kids by the time I was 30 or 31. That didn't happen, so I pushed it back to 35....then 40...then, ultimately, "if I'm pregnant with the last before I'm 40", then "if I'm pregnant in time to have the baby before I'm 41"...and, ultimately, dd2 arrived 12 days after my 41st birthday.
In all those years of secondary infertility and miscarriage and everything else, I was never able to make peace with it. The oops pregnancies and twins (two of each) in my immediate family certainly didn't help, but it was more than that. I wanted children - my own biological children - and that was all I wanted. I have less than zero interest in working with kids, or fostering or anything like that. I know some people take comfort in that, but it would have just been salt in the wound for me.
DH originally told me that ds2 would be the last...while I was in L&D, being prepped for the section. I was so angry. My reasons for caving on the c-section in the first place, strange as it seems (I wasn't thinking logically at that time), were interwoven with my plans for another pregnancy. I felt betrayed and abandoned and totally alone.
We talked a lot over the next year or so. He finally agreed, and...we had Aaron. And, the next day, he said we'd try again. Then, he changed his mind. And, we finally came to an agreement, and we have dd2, who is the light of our lives and has pulled the whole family, including dd1 and ds2, together in a way I can't even describe. But, it was a looonnng haul to get here. There are still some stresses that are directly related to having different views on things. (I will mention that I didn't talk him into it. We had a lot of discussions, and he knew how I felt, but I also worked really hard on not making it into a fight or whatever.)
Anyway...I have no answers. I never did make peace with it. It caused me a lot of pain, and a lot of anger at times, for a very very long time.
Oh - a few people commented on how the other child(ren) feel about mom wanting another baby. I can only speak for ds1. The whole time I was ttc, he knew about it. He knew about the miscarriages. He was crushed. He wanted a sibling so bad. I think he lit up even more than I did when he first laid eyes on dd1. He wishes I'd been able to have kids sooner, because a 10 (or 12...or 16) year gap makes some huge changes in the sibling dynamic. But, he adores his siblings and is thoroughly enjoying dd2. He knows how much I love him, and that I wouldn't change him for the world. He and I have talked about all of this. He thought I was slightly nuts to have dd2. He's glad I'm done, because the last couple pregnancies, the c-sections, and losing Aaron, have all taken quite a toll on me, both physically and emotionally. But, he's never felt "less than" because I wanted more kids. (He told me recently that his future wife is going to love that he had younger siblings, because he's way better with kids than most guys his age.)
For those of you who asked - I've met the OP a few times. Watching her interact with her kids, I can't even begin to imagine them feeling as though they're not good enough for their mom.