Hard time seeing friends and family get pregnant... not on purpose either

I've been having a rough time accepting my sister get pregnant twice, me miscarrying and my friend and cousin getting pregnant and non of them had to try. I feel like I'm whining and whatever but it's sad feeling like I can't ever get pregnant and depressing when you miss your period and think you're pregnant and then comes mother nature to trick your heart .. is anyone else in the same boat or am I being too selfish? I've been TTC for 3 years with a miscarriage @ 6 weeks (we didn't know we were pregnant, but still broke our hearts) we have been trying for 6 months since the MC ... hoping for our rainbow.