Can my mother in law stays at my house without my consent

Both you and your wife have equal rights to allow visitors in the house. While you may certainly express your disagreement, you will not be able to keep her from having her family in the home. However, you said you have an open divorce case so the judge could order that one of you have exclusive use of the home. If you get exclusive use of the home during the pendency of the divorce, this issue would not be a problem because your wife would not be living in the home.