Can a parent legally hold a childs medication from them if the child is 18?

first off we live in Alabama and my girlfreind's mother is making her life a living hell, and she is wanting to move out but she is scared that she wont have finical aid and that her mother wont give her her medications, in speculation if we were to get married seeing as it does not require parental consent at 18 in alabama and we become independents she would be able to get her medications from her mother without drama etc and we would then be able to use our tax info to get finical aid for her am i right in any way of this?