Can a division of property settlement be lowered due to medical condition i.e recent stroke?

The decree reads: since the petitioner (me) is being awarded all interest in his military retirement benefits in accordance with the terms and provisions set out above, the petitioner shall pay respondent (ex wife) the sum of $600 per month as long as both the petitioner and respondent are alive. Now that was 11 yrs ago. I have since suffered a stroke and now have dementia and suffering mini strokes. In texas due to my medical condition can I seek to have it reduced since I can no longer work?