People who can only have one kid to medical reasons how did you accept that?

Long story short, I have one little girl who’s 5 in July she starts kindergarten this August. My husband can’t have kids biologically so we did IVF with donor sperm And we got 2 girl embryos that were genetically tested normal , I transferred my first girl embryo resulting in my daughter who almost 5 and I just used my last embryo January15th it resulted in a pregnancy but it doesn’t look like it’s going to lead to a birth and I’m probably going to have a early miscarriage. No known reason sometimes it just doesn’t work I guess. I thought about doing another egg retrieval but all of this ivf stuff has been such a roller coaster. I was really hoping my last embryo would stick so I could give her a sister. I have come to the terms if it does fail just accepting my first daughter as I didn’t think we would have any. But I do feel sad I swore I was one and done then I got the idea of giving her a little sister and being my last embryo is failing. I have to decide if I want to go through all the meds and trauma or just accept my blessing and be happy I had one daughter which I knew I always wanted. So if you could only have one child how did you accept you would never have anymore? I want to move on and accept the second one didn’t work and atleast I tried.