Can't fall pregnant & sad. :(

Hi all! 

I've been feeling a little down lately.. 

I can't fall pregnant.  we've been trying for ages! A doctors Hasn't actually told me I can't have kids. But I'm startin to think I can't. And lot of my friends and family are having babies. I wanna be happy for them, but I can't I just wanna cry.  

Is there a way I cah get over this feeling