Just another bitter rant

The other day I found out that my fiance's little brother, who is sixteen and who has basically dropped out of high school, got his ex girlfriend pregnant. My fiance's mother is so excited for a grandkid that she won't stop posting about it on facebook. It's making me so bitter that his brother got a girl pregnant when my fiance and I have been trying for a year, and are doing some tests with a doctor to see what's wrong. I know it's not my place to look at his situation and feel bitter, I know that when my fiance and I do have our first child it'll be a beautiful experience and all planned out but I just can't help feeling the way I do.