Texas Marriage State

Texas marriage state
How long can i live with my girlfriend until it is considered common law marriage in the state of Texas?

I jus need to know how long in the state of Texas

it not how long but if u and ur girlfriend consider urself to be married to one another, call each other husband and wife, file joint tax returns, she uses ur last name ya’ll are common law married if u need more info check out this website
http://www.unmarried.org/common.html