TTC but having trouble?? Jealous of other pregnant women :(

Candi
Me and my husband have been TTC for almost 6 months with no luck. I had a wonderful dream that I was pregnant with a little girl. Then the very next morning my sister found out she is pregnant. I am happy for her but I am also jealous :( anyone have any advice?? I want a BFP so bad but I try not to stress about it... Any advice??