RSV. Thanks to careless parents

Its 4:11am and I am laying in the hospital next to my baby girl who is stuck in the picu. I'm so full of different emotions, failure, hurt, but most of all anger. BACKSTORY: My brother in law and his girlfriend moved in with us 11 months ago, his girlfriend kept bring her kids over to my house sick EVERYDAY. When my daughter was born a bunch of drama on their end happend and well brother in law left and moved in with his sister. Well fast forward to 2 weeks ago when my sister in law kicked him out with 2 kids of his own with absolutely no where to go. WELL my husband let him move back in with us, again girlfriend shows up with him with her 2 kids, she let us know her son has gotten over pneumonia and pink eye, well a couple days ago my daughter had pink eye, then the past week hasnt slept but maybe 30 min at a time, tonight she couldnt breathe my husband and I were both terrified so we brought her to the hospital and that's where we just found out she has rsv and cannot come home. When I was talking to the doctor he informed me more than likely the girlfriends kid had rsv in which she didnt take care of which led to pneumonia, which also probably isnt cured which is how my daughter contracted it. I AM SO PISSED OFF. I'm not even sure how to function I am just so mad, and I want so much to yell at my brothers girlfriend for exposing my children but know my brother will leave with his 2 kids and they will be 100% homeless. Any advice on how to handle this situation. It just really upsets me how can a mother not take care of her child enough to let them always be sick? Or let an illness get so bad to the point of pneumonia especially since her just turned 1. My daughter is doing well but seeing her this way ugh I wanna kill someone. Hopefully we can go home tomorrow but arent holding our breath. First picture is when we first got here, second is after they got oxygen on her and cleared her lungs.