You are a month to month tenant. Make no mistake about that.
The Texas landlord tenant statute says that all she has to give you is one month's notice.
https://law.justia.com/codes/texas/2...-8/chapter-91/TITLE 8. LANDLORD AND TENANT
CHAPTER 91. PROVISIONS GENERALLY APPLICABLE TO LANDLORDS AND TENANTS
Sec. 91.001. NOTICE FOR TERMINATING CERTAIN TENANCIES. (a) A monthly tenancy or a tenancy from month to month may be terminated by the tenant or the landlord giving notice of termination to the other.
(b) If a notice of termination is given under Subsection (a) and if the rent-paying period is at least one month, the tenancy terminates on whichever of the following days is the later:
(1) the day given in the notice for termination; or
(2) one month after the day on which the notice is given.
The statute doesn't require written notice. Remind her that the law gives you one month from the day she told you that you would have to leave.
She cannot lock you out. That would be illegal.
See 92.0081, 92.009
https://law.justia.com/codes/texas/2...-8/chapter-92/
You need to look for another place to live and don't wait until the last minute. Once the month is over she can file for eviction in court and you certainly don't want that on your credit report.
A word of caution. Once you move make sure you call the water, gas, and electric company to take your name off the accounts and send you final bills to your new address. And follow up every couple of days to make sure it's done. Otherwise you might find yourself owing thousands years from now.

