Do you ever feel less than?

There is a woman at my office who was due around the same time I was. She's starting to announce that she's pregnant and I'm hanging my head, feeling not shame but less than. I can't even look at her in the eye. She's not bragging, she has no idea I had what she had then lost it. 
I'm not trying to dwell on the shoulda, woulda, coulda's but I'm just feeling... less than. She is full of excitement and I'm full of pain and emptiness. 
It's hard to explain but have you ever just felt like you're less than?