I really feel for you. Sounds like your in a tough decision here and the fact that you have already looked into leaving but can't for 6 to 8 weeks.
As much as you love your husband, do you respect him as a father? Sounds like he has no balls in teaching his child how to behave or show you lack of respect for you as his wife or step mom to his son.
Well, your daughter should come first, she needs you and doesn't need to be harrassed by a 9 yr old brat. If your husband is not helping or taking control on the actions of his son - then it's your husband & your step son who is making the decisions for you to move out. From your prevoius posts and now this one - you have put up with this long enough.
If you want one last effort before moving out....is there anyway when the boy comes to visit that you & your daughter can be unavialable? Meaning go out shopping, dinner, visit friends, get out of the house when he comes to visit - if he is spending the night...It's your husband who should be taking care of the boys needs...Not YOU! Remove yourself emtionally from the boy.
Ignore Him - walk past him like he's not there. Sounds like he wants all the attention and he's getting it in any way he can. Tough Love, the kid may really be seeking love from his father and is taking out neglect of this on you and your daughter. Go out for an evening to the movies, ice cream, or a drive around...Your husband should be responsible for his son...NOT YOU.
Hope this helps.