Best friend is pregnant

My best friend got pregnant in February.. I’ve been trying to conceive since November. Im very happy for her but also jealous. And she knows how much I want to be pregnant. Yet she’s asking me to plan her reveal party. Constantly telling me different things like the color they’re painting the nursery and the doctors visits.. I want to be happy for her and I am but hearing her talk about her pregnancy makes me sad. I feel like the shittiest person on this planet for this and Im not sure what to do. It’s just making me more depressed every month when I get my period. Please don’t make me feel worse... I already know this is horrible of me to feel jealous and upset..