Am I a horrible friend?

So my best friend has just told me that she and her partner of 8yrs are trying for a baby. Sadly she lost a little girl at only 3 days old with her ex about 9 yrs ago so it's taken her some time to decided to start a family with her new partner. They recently got engaged and I couldn't be happier for her. My problem is that I have been TTC for a few months now and I am worried that if she falls pregnant before me I will resent her and avoid seeing her. I want to be supportive and be with her during any major event in her life but I can not help feeling I might get jealous if she is more fertile than me. Is it a horrible thing to want to at least fall pregnant together?