Am I wrong?

My SOs sister keeps making me feel guilty for being pregnant. This is my first pregnancy, and though it was unintentional, my SO and I love our unborn baby so much. She gave her child up for adoption because she'd rather drink an go out, etc. I know she regrets it, but I feel like whenever she's around I have to stay quiet about my pregnancy and avoid the topic when she's home because she makes me feel so guilty for keeping by baby just because she chose to give up hers. She's around often, and I am tired of feeling bad whenever I'm around her because of her constant guilt tripping and rude comments...am I wrong if I openly discuss my baby when she's in the room? Am I considered rude?