I can imagine how this could make you sad. I wish you all the best in your efforts. As half of a childless couple after 30 years of marriage I can tell you the way we have coped was to hang out with friends who don't have children because we had very little in common with them any more, and eventually our friends who do have children became empty nesters, so are back to being reasonably childless, except if their kids turn out to be bums and move back into the family home and sponge off the parents, then we feel superior.

Looking back, if we had both wanted children all that badly, we should have adopted some. There are many reasons why people want their own biological children, but if that isn't possible and you are just tearing yourself up, maybe you should consider it. Hugs.