LJ,

In the past, before the advent of reproductive tech, couples who could not conceive would give up trying, adopt, and then, miraculously, conceive without further ado. The explanation was psychological - once they released their expectation, the little miracle happened right away. You have yourself said all the right things, how the worry cannot be helping and how the fun is being taken out of the whole deal.

Also, somewhere, a long time ago, I read that the peak female reproductive capacity happens at 25 and not at 20. Another thing is that if your menarche was late, your reproductive system might still be maturing. When did you have menarche?