When is it too much

Today, I'm sitting here so depressed and crying over another failed cycle. I can't believe how I let myself hope and get excited over this finally working and after 6 years and 72 periods, we will finally be a family. I'm hopeful that the surgery, injections, hormones and more medical test than I can count have finally paid off. Then reality hits and my body lets me down and after 28 days of hoping it's another negative pregnancy test and another painful period. So now I'm having to ask myself when is it time to face reality and just give up, to finally come to terms that I'll never be a mom.