pcos frustration

I was diagnosed with pcos in December after tyring to concieve for 3 years with no luck. I was recently started on Clomid and Metformin after 2 rounds of Medroxyprogestrone did nothing for me. These last 3 years have been full of nothing but heartbreak and frustration. I'm hoping now that we've figured out the problem we can find a solution. I am "mommy" to an amazing 4 year old from his fathers previous relationship.I love that boy more than anything in the world, but I still feel like its not enough. Like I'm missing something, almost empty. That makes me feel horrible because hes my world. I guess its just not the same because hes not biologically mine. 

I'm just a mess of emotions and I'm not sure how to deal with them.I feel like nobody in my life understands because they've never had to deal with this.