Thanks everyone for your words of wisdom. Yes, i am an inexperienced landlord. This tenant was moving to Houston from another state and had no place for her and her teenagers to live in. She begged me to let her move in right after my house passed the inspection. I felt sorry for her and skipped the neccesary steps.
Anyway, I called the Housing, didn't get to talk to the case worker but the operator told me that she didn't see any reason that I couldn't evict this tenant. She would leave the notes to the case worker to call me back.
Yesterday, I came to the house and gave the tenant the 3 days notice letter. She didn't look surprised though, asked me about her deposit and told me that if i filed the eviction, the judge would give her 30 days to move out. I just simply replied that we will see what the judge says and walked away.
I am going to take Joel's advice to try to meet the case worker in person next week.
Thanks again.