Andy Man, this is tough. @jsmart
is right. Virtual hug to you.
So, what is your plan here? Not the plan to get her back, but the plan for the separation and divorce and custody of the kids. Forget what wife wants. What is that you will insist upon?
There is no limbo allowed. If this separation continues it moves to divorce - at YOUR insistence. Any prolonged separation - wife gets house and kids 90% of time, you live in rental with kids two nights a week - is not going to cut it.
Put all your chips in. Go to war with your STBXW over the assets and kids. Not in a revenge or vindictive way, but for equal assess to the kids. Right now your wife has nothing to lose as she knows you are kept at bay by her manipulation. When she realizes that her bubble and her plans for this are threatened by this now dominant man, she will react.
I don't buy this cheating on her a hundred times crap. It is internet porn. As long as you were not cheating her out of sex by doing it, it is survivable. Did I read that sex dropped off to almost zero? No wonder you watch porn. Many or most guys do. Porn built the VHS industry and much of the early internet.
She asked you if you were still attracted to her? Really?? WTF?? BTW, what did you say?
Yes, she is testing you with EVERYTHING she does. If she wants divorce then she should have moved right away or follow whatever are the UK laws. Preempt her by filing for divorce now and 50% custody AND the house.
Yes you are going to date other women. If nothing else just for coffee. Play it low key and tell them up front you are separated and moving towards divorce. If they reject you it is because you have too much current baggage (still married, right) not because of you.
Not sure what you told the counselor to make her turn pale. Does not matter.
So again, what is your plan? Long game, right? Fight for your kids! THAT is the kind of man, the only kind of man, your wife respects.
Print out the divorce papers or get a UK lawyer to draft them. Then present wife with YOUR separation demands, show her the papers, and if she does not agree, you file. Do you know what her first reaction will be - respect for you. Remember, divorce papers does not mean divorce. YOU can stop the process at any time.
Good luck, eat well, and work out at the gym. Other than the kids and your job, that is you top priority.