Before I pick-up the phone (and that's IF I pick-up the phone) - I repeat a few slogans, Easy Does It; Let Go & Let God; Breathe, Just Breathe; and God do for me what I can not do for myself. And also remind myself that no matter what me & my God are going to be OK regardless, even better than OK.
Then, you can always end the phone call at any time you feel your serenity slipping away.
One Day at a Time,
Peace,
Rita