My husband refuses to separate himself from his parents and siblings. Should I divorce him?

[Brittieboo]

I hate to say it, but if you knew this and you had issues with this before marrying him, then you should not have married him. There is no way to change a person. You can simply accept them and love them for who they are.
Your husband sounds like and incredibly selfish person, though. It is incredibly unfair of him not to stick up for you and to make you seem like the bad guy to his family. He seriously needs to take a step back and look at what his priorities are.
I would recommend talking to your husband again and telling him that you feel like you are coming second to his family and that you can't take it anymore. Let him know how much it is effecting you.
If this does not work, try sitting down with his mother. I'm not sure what your relationship with her is, but if it is already a bit rough (it sounds like it may be) then you aren't going to hurt anything by doing this. Tell her that you love spending time with their family and that you really appreciate them wanting to be such a large part of your lives, but that you need some privacy, too. Try to set up times that are just for you, your husband, and your daughter to be alone. If people try coming over during these times, politely tell them that you are having family time and you will call them later when you are not busy.
If none of this works, then I would say that it is time to seek some couple's therapy first to get things out in the open and perhaps help him to see what he is doing that is messed up from a different point of view. Then, divorce would be a very very very last resort! Good luck!