The issue here is that you have so much contact with him. As Hannibal Lecter said "We covet what we see everyday" (LOL but true). You deal with him a lot.
No contact allows us to not have it thrown in our faces all the time. Your situation is more complicated because you WORK together, you aren't just spouses. My advice would be to quit this job, but that takes time and may not be in your best financial interest.
You need to lay boundaries and do your best to have has little contact as possible. I would change the method of communication. No more phone calls. Everything must be email or text. No more meetings with him. No more stop by and drop off in person.
Until you start working the steps you won't feel what you are looking for. Find a sponsor and do it. You keep saying " I haven't found anyone I'd like to have as a sponsor" . A sponsor is a teacher, not a friend. The qualities you need are someone willing to do it and beyond that it doesn't matter. Pick one and start.
Lay down boundaries of communication ASAP. If you don't talk to him on the phone, he can't hang up quickly and make you feel bad. Get the picture? Take your power back.