I too work with my exAbf/F. It's difficult. It makes it very hard if not impossible to detach. However I refuse to leave because it's not likely I'd find another job like mine so close to home and I have great benefits. Fortunately for me and my A we have always kept our relationship at work very professional. And we work in separate depts. I have read that A's often think of work as very important to them, (if only for the money to continue drinking). Hopefully your ex considers work important and you two can at least both individually focus on your job.
You should read many of the threads on here and you will find that it's really for the best that you're away from this man. I think we all have some hope that our A's will one day see the light and come back to us. I also think that it's not wrong to feel that way. But regardless you must go on with your life. Everything always works out if you let your mind relax and turn things over to your Higher Power.