Am I just overreacting?

So my sister is pregnant with her third child, but here is a thing! She said that in order to have sex it's only to procreate. But here is the thing she said the child isn't planned. So I told her she is in sin than. So my problem isn't that she is pregnant with her third child. My problem is she hardly can't take care of the two she has and is going to have another. She really can't protect them from the father's physical abuse. Now another thing is she said she is also having another baby because she misses her two baby being that small. Now as many of us on here that struggle with trying to conceive or maintain the pregnancy myself included. I spent over 10,000 in fertility treatments and medication. What upsets me is she had the audacity to say if I was mad that she was pregnant and that I couldn't get pregnant. Am I wrong for not wanting to speak to her and having my space for a little bit.Let me just add I absolutely love and adore my niece and nephew they are the light of my day. And i wouldn't mind her having another child if she actually could afford it and protect he or she.