I have a roommate who is not on the lease, that I wish to leave. What are my options if she refuses? I'm in Alabama

If they are not on the lease you have with YOUR landlord, then you are their landlord. Since you have no lease with them, they are a month to month tenant. They can be evicted following the normal eviction process. First send them a notification that you are terminating the tenancy after one month. If you give them the notice today you can make it effective 3/1.

If they have not left by 3/1 you need to file for an eviction order in your local housing court.