As far as the foreclosure is concerned, if you are unable to arrange for payments with your current lender, then the foreclosure may occur as scheduled on the first Tuesday of the month. At that point the new owner will be in touch with you to make arrangements for your vacating the premises.
Typically, you will have at least 30 days, but circumstances may allow up to 90 days in the case of homesteads, as Guy mentioned.
Time has come for you to investigate finding another place to reside and figure out how to get your personal items removed.
Lease to own is a practice discouraged in Texas, because it led to abuse in the past. Now, sellers are required to disclose the financial aspects annually to the leasing buyer, which is the source of headaches and potential liability for the seller. Only an attorney can write up a contract that does not close within 180 days of execution (this precludes Realtors from writing it up on standard forms).
In the few lease-to-own transactions that are done the terms definitely favor the seller and provide for only some portion of rent payments to be credited to the leasing buyer. Your attorney can best explain what approach will best protect your interests and explain other options that are probably better suited to buyers unable to close a purchase within 6 months.