Heartbroken

My significant other’s sister called us earlier to let us know that she’s unexpectedly expecting a baby, about 5 weeks along. Please don’t get me wrong, I’m so happy for her, but it was like a huge kick in the heart 💔 I did everything I could to be the best mom I could once I found out I was pregnant: I cut back on caffeine, I ate insanely healthy, didn’t drink alcohol, drank lots of water and started light exercise yet I still lost my baby. My SO’s sister smokes like her life depends on it, only drinks coffee, has diabetes and hypertension.....I can help but to think “why her and not me?” I just need to vent a little. My SO doesn’t fully get why I’m hurt by her announcement. I’m hoping that after I have my self pity party tonight, I can have a better perspective tomorrow.