PS, You and your H are still in a transition period. To me, this is the hardest stage of all. He is still clearing, and you are still recovering from the trauma of it all. It is natural to seek out reassurance, but that kind of thing triggers the guilt and shame within H, and he doesn't really give you the kind of response you need. And then you become angry with yourself for upetting the apple cart, which leads to more anxiety that there will be setbacks. This is all par for the course.
The only thing I can tell you is to hang in there...you are really doing well. It is unrealistic to think that you should remain quiet and keep your fears to yourself. Your H is going to have to provide more support for you, as you work on your own anxiety ( which you are doing). For now, while he still is sorting through things, try your best not to bring up OW. He is trying, I am sure, to put her on a far shelf in the back of his mind, waaaaay far back. If you want reassurance, ask for support from him. Practice this: "H, I am feeling kind of off right now, can you give me a hug?" Ask him to bring dinner in, pour a glass of wine, make a bath, etc. Or, take the distraction/fun route, rather than the nurturing, by asking him to go for a walk with you, renting a movie, etc. The point is, get his help without bringing OW to light. Keep her in the dark where she belongs.
Oh and one more thing, Pleasepleaseplease do not go near the cell phone. It is trauma to the brain and can send you into a downward spiral. View it as the poison it is.
