In-law problems and husband won't stand up for me?

I'll try to make this as short as I can. Basically over the last few months the relationships between me and my in-laws (Mother/Father-in-law and Sister/Brother-in-law) has been fading and I honestly can not stand the sight or thought of them. My parents-in-laws have been going through a major separation issue and both have taken advantage of me and my husband and FIL even lived with us for 5 months and basically used us and my husband kicked him out on a bad note and since we put a roof over his head my MIL hates us for doing it after they made a mutual decision for him to leave. Now my SIL and BIL are arguing because we both got pregnant at the same time and they have always been the signature "copy-cat" couple with weddings, cars, houses and now this and I had it. Which she then flipped out and told me to go to hell and her and my BIL both started haring me with emails, voice mails, and texts. My husband has stood up for me some what but now I have heard my BIL and SIL have been discussing our issues with their friends and I am known as "Psycho" between them all. I told my husband that he needs to say something to them as I feel like his family has walked all over us and he is very good at agreeing with me but when it comes time to say something he backs down or plays nice guy. I know he doesn't want to be in the middle but to make matters worse I am 11 weeks Prego with our first and I can not take the never ending stress from them but he wants me to calm down for the sake of our baby but never sticks up for us to their faces? I'm sick of it and feel like I am trying to juggle my own battles and their constent bitterness and he can't even stand up to them for me and his child? He agrees with me behind closed doors and then pretends to their faces, I don't know what to do anymore and it's causing stress on our relationship! Help?! Oh and I haven't spoken barely to my MIL or FIL and haven't spoken at all to my BIL or SIL since everything has blown up, why put myself through that when I'm all alone in this?