My wife and I separated, she moved out as I had bought the house before we married, and have been living in separate homes, and I have been paying her a monthly alimony since then, am I legally required to pay her that monthly money or any other money before or after getting a divorce?
Before divorce, the answer is no. After divorce, you will only be required to pay if it is ordered by the court. There is no alimony in Texas, but there is something called Spousal Maintenance. Spousal Maintenance isn't automatic. It will only be ordered by the court if certain requirements are met by the requesting spouse.
Workers' Compensation Lawyer
I agree with the other answer and would add that in most states this type of thing would be ordered in temporary orders that come about after the filingof the divorce petition. At this point what you are doing is voluntary however in my state the judges seem to like to order the parties to keep paying what they are paying when the issue comes up for temporary orders or even permanent orders so keep that in mind.