TTC - need good vibes

I am really struggling because my boyfriend and I have been trying to conceive for nearly 3 years now & no luck.. I'm only 23 years old and I'd say fairly healthy ?? I feel horrible because everyone my age is getting pregnant and I want so badly to be happy for them but I can't help but think .. why not me :( I pray constantly but nothing and I just really don't understand. I want this so badly