Hi and welcome!
I am really sorry to hear about your relationship troubles. That is really a hard thing to be going through...and interpersonal issues certainly trigger my anxiety as well!
it is great that you are seeking to use coping skills to manage your anxiety during this time. Great step, and I am sure that you will find much benefit in this.
There are some exercises that you can do while at work, such as controlled breathing patterns, short meditation sessions and progressive muscle relaxation.
https://www.healingwell.com/community/default.aspx?f=9&m=104206
Practice these at home, and they will become so second nature, that no one will even know when you are doing them in public.
You can find instructions for these and lots of ideas for self-help here:
Keep posting with us as well. We understand and are here to listen anytime.:)
Best wishes and talk to you soon,
Scaredy Cat