If you think you will have a bad adrenaline rush when you are in the presence of your ex - if you tend to et shaky and sweaty palms and rapid heart rate - talk to your doctor about the possibility of taking a low dose beta-blocker (unless you have asthma - it's contra-indicated for asthma).
This is how we treat stage fright - the patient takes a low dose (like 10 mg propranolol) of a beta blocker about an hour before performing. Beta blockers are blood pressure medications which work by blocking adrenaline effects. At these low doses, they can lessen the racing heart/sweaty palms/ shaking hands that some people experience when under stress. The lack of those physical symptoms, in turn, makes it easier to feel in control. It might help you feel calmer and react less to your ex.
I called my dr and she gave me xanax. Wasn't my first choice but that's what she gave me. Dummy me took a whole pill just to see how I'd react and it put me down for 24 hours. Not fun.
When my anxiety gets high I talk too much and that is not a good thing.