Should I be sad.

So my husband and I have a a 3 year 9ld married seven years we tried for 4 years to have a baby, fast forward my husband's cousin has a child who is 6 months younger than ours, she expressed to everyone even her husband whom she has a shot gun wedding that she didn't want to have kids including the one she has. So for the last 2 years and 6 months my husband and I have been trying our son is 3, to have another baby, one miscarriage other than that no luck. She called to today to inform everyone that she is pregnant with baby #2, just listening to her own the phone she didn't sounds even remotely happy. I guess the question is, I'm sad because we've been trying for almost 3 years, hoping and praying for a miracle, and its only been heartbreak. And she didn't want her first baby and now she's pregnant with #2, I can't help but be angry that those including myself want a baby and it doesn't happen and those that don't it happens. Do i have a reason to be upset or am I overreacting?