Help. Boyfriends weird sister.

So my boyfriend has 3 sisters and two of them were crazy meth addicts. One of them still is. Which makes me mad is she's doing meth, weed and smoking cigaretts all while she's 5 months pregnant. And the guy who got her pregnant is a 54 year old drug dealer who doesn't have a real job (She's only 24) I don't want to use her real name so I will just call her Jessica (Note I have nothing against anyone named Jessica that's just the most common girl name I could think of.) Jessica always talks about my boyfriends ( her brothers) body. "Oh m brother has such an amazing body! Like don't get me wrong he's my brother but damn it looks good you know what I mean?" No I don't, I would never talk about my own brother that way. Makes me freakin weirded out. Am I wrong in thinking this way?