My mother paid to have her home built and added me and my step father to the deed she passed and I need to move into the home can I get him out?

My mother built her home with her money her self and put me on the deed if something ever happened to her she wanted me and my children to have it for my family. She also added my stepfather but he had a massive stroke and became disabled and my mother took care of him and then she had a massive stroke and suddenly died this year and my step father not a mother later started staying with an ex of his all the time I tried to get into the house to get my mother's belongings and try to make arrangements to start to move in and now he has moved this woman in to my home and I don't know what to do my mother left this home for me and my family and he has somewhere else to go but he is also on the deed but because of his mental state he will not do anything unless this other woman tells him too and I don't know what to do.