If I divorce my wife in Texas what portion of my annuity will she get?

As a general rule she'll get half of whatever portion of the annuity's value was accumulated during the marriage. For example, if you were already drawing benefits when you got married, your spouse is probably entitled to nothing. If the annuity is an employee benefit and you were married to your spouse for the entire time you were earning it, it's a presumptive half-and-half split. You need a lawyer if you're getting divorced.