I am sorry that you find yourself in this position. It's awful, we all know.
I don't know if it's possible to get over the scope of this betrayal.
One thing that my therapist said when I was seeing one was that there are horrible things that happen in your life that you never get over, and maybe you don't seek to get over them, per se, but rather they just incorporate into your life like everything else that has happened in your life and you just learn to walk beside it. I dunno, it spoke to me for some reason. It took a little pressure off to "get over" something so monumental, gave me permission to not "get over" it. At the time, I felt like yes, maybe I can walk beside it, I don't have to forget it. I also had a visual that in walking beside it, I can decide how safe it is or not to walk closely beside it, you know what I mean? Like maybe at this fresh point in your learning (or mine at the time), you can consider that what you're trying to walk beside is not safe, and maybe you need to be prepared to scoot away, maybe you need to wear an imaginary helmet or other protective equipment until or when it is safe to walk near it.
It would be, perhaps, safe to walk near it when your WH does the work to make you feel safe. And when you feel you have gotten all of the information about this time in your life to be able to process what exactly it is you're dealing with. You've gotten more out of him about what he was doing, but you've got to be prepared for more, unfortunately.
FWIW, my FWH also used prostitutes. I found out in 2013, we are reconciled. I wish I could say I'm not wary. I wish I could say I'm entirely happy with that decision. I think that I will always be at least somewhat on alert although I'm not checking phones routinely or going through every move he makes at this time. We all have to decide if it's in our best interest to stay or leave, and everyone's circumstances are different.
Me - BW DDay - May 4, 2013
And nothing's quite as sure as change. (The Mamas and the Papas)