It sounds like the close call of nearly loosing your brother on top of being preggie has you run down and feeling really low. Thank god your brother is alright I wish I could say the same for my sister and her hubby :( 7 mths after giving birht to my 3rd child they were killed in a horrific car accident and I never had the chance to say good-bye. She was my twin so the emptyness I feel I can't put into words.
Don't worry yourself with that other girl as looking for someone to blame will not make you feel any better (trust me on this) just cherrish every moment you have with your family and think of that little gift from god you have in your tummy. He/she needs you to be as healthy and happy as you can be.
I'm now 26 weeks preggies with my 4th and trying to get on with life and sometimes I feel this little one is a true gift from my sister to me.