As a resident in Texas, I would like to know how to properly evict a 22 year old "drug addicted" son from my house whom does not pay rent or expenses. This individual has quit today and walked out without completing a drug rehab program that was set up and purchased for him. Also, my son has threatened personal harm against myself and the home if not allowed back into the house, so I would also like information concerning a restraining order as well.

Since he has threatened you, you don't need to evict using the usual formal procedure, and you call the police station or local courthouse to see where to get the RO. You need some sort of protection in addition, however. The RO only works if he complies with it, or you can get police there fast enough if needed. Relatives, even male boarders for a while. Sorry for your troubles.