Hi OP. Sorry you are going through this. I've been through 5 years of fertility treatments and I'm now finally pregnant from an FET.
I wondered, have you had your embryos PGTA tested, or considered it?
That is one thing which I truly believe made a huge difference to us.
Most miscarriages in the early stages, and embryos that do not implant, are due to chromosomal abnormalities.
Having PGTA testing vastly reduces the chance of that - it basically filters out embryos with abnormalities, so they will only transfer a good quality, normal embryo. Embryos can be graded as good quality but still have abnormalities that would only be picked up on testing.
I got pregnant on the first FET we tried with a PGTA tested 'normal' embryo, and I'm now almost 12 weeks. I've never been pregnant in all this time, so I'm absolutely thrilled.
Interestingly, only 2 out of 5 good quality embryos that we tested came back as normal (and we are using a sperm donor - I don't have fertility problems myself, our issue is male factor - I am healthy and in my mid 30's). Apparently, this is a normal amount. More embryos than you would think have abnormalities of some kind, even in normal healthy individuals. This is one reason why even fertile people don't get pregnant every month they try, and some have miscarriages early on.
If we hadn't done PGTA testing, there would have been a 3 in 5 chance an abnormal embryo would have been chosen, and it either would not have worked or I might have had a miscarriage.
It can be expensive but I really highly recommend it - it also gave me so much peace of mind once I actually got pregnant that I had a reduced chance of anything going wrong - and so far I have had a textbook first trimester.
Good luck, whatever you decide, this journey is a horrible one that no one would choose xx