The place where a couple resides is termed a "marital residence." The sheriff and the previous attorney that you've spoken with are correct. Since you live in the residence, your father-in-law can file a dispossesory (eviction) petition to remove you from the home.
You can request that the Sheriff's Department accompany you to the house to get personal belongings i.e., clothes, personal jewelry. Keep in mind that a deputy is not going to stay there all day while you move stuff out, however.
If you are ready to file an action for divorce you can request a temporary hearing at which time the Court will determine on a temporary basis who has temporary use of the marital residence.
Hope this helped, and good luck.
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