Why not me

Everyone and their brother including my own brother are getting pregnant and having babies....... Its in my nature to be ecstatic for them but I can't help but feel jealous and upset that my husband and I have been trying for 3 years and not even a glimpse of hope has risen just this year I was told I have pcos and am diabetic so its been a super depressing year for me. Any words of wisdom or advice would help me at the least