I don't mean to be jealous but i cant help it

me and my fiance have been trying on and off for nearly a year for a baby. my best work friend knew about it and decided through speaking to me that she would try too. she just told me she is pregnant but I can't help but be jealous it took her three months... it feels like it will never happen for me and I am so sad. I am happy for her but I am so depressed... 😶