Friend – I think you are doing one classic mistake most betrayed spouses tend to do: YOU are trying to end her affair, when it needs to be SHE that ends it.
In banning OM, deleting his profile and all that... It’s like grounding a teenager from the school dance, and she’s feeling it’s all unfair and thinking of crawling out the window. You are the ogre preventing her from her fun. From getting her fix.
As-is you can’t compete with the OM. He’s fantasy. He’s the White Knight on the White Horse riding into the sunset. She’s heard you fart, seen your pimples and had arguments over bills and utilities with you. Compared to Prince Charming – you are mud.
As contrary as this might sound then your best bet is to set her totally free.
Yes – If she choses to contact OM and masturbate to printouts of his gospel... let her.
Only not as your wife.
Consider doing this:
Tell her that you love her and thought there was nothing you wanted more than this marriage. However – you have realized two things:
If her happiness lies with OM then because YOU love her you would be holding her away from happiness by denying him to her. You have realized that with time you will recover, but that you can never totally have her if she is forced to be with you. Therefore you are setting her free to be with him
The other thing you realized is that you don’t share your wife. If she wants him – then fine, she can go be with him. But not as your wife. Until and unless she willingly tells you that she wants YOU and tells you why she wants you... you are simply assuming she has chosen OM.
Therefore you are absolving her of any marital obligations, and are starting the process of you two terminating your marriage. There is no rush – it’s not as if you will file tomorrow. But you two better start preparing for the inevitable split so she can freely follow her "love" for OM.
Make it clear that there is a process, it takes time, and it’s generally fair and should prevent either of you taking advantage of the divorce. But it’s a process you are starting off on and the further along you go the less likely you are to stop.
Make it clear that she has this window of opportunity. She CAN let you know AND show with verifiable actions that she choses you. But that’s totally HER choice. You are not holding her from OM. Make it also clear that even if she does chose you then you are skeptical, and it will take time before you are convinced she might be committed to this marriage.
Then simply stop arguing. You could ask that she be discreet in communicating with OM. Ask that she maybe goes and does so in the car and not in the home. But that she is totally free to go date him or whatever. Only... not as your wife.
Then move on. Go make a sandwich or whatever. You have stated your case, made your stance. It’s now her call if she choses you or OM.
Let stakeholders know. Tell those that might impact her that you are probably getting a divorce because your wife has chosen her online lover over you.
What all this does is it moves OM from fantasy to reality.
All of a sudden there is rust in the White Knights armor, and his horse smells of... horse. When he starts pulling back (because he’s only after some digital-ass), or when he asks her to pay for his ticket to see her, when her sister starts asking her what the f... shes thinking... the fantasy becomes reality. When she realizes the family home will be sold, that she needs to get a better job, that you are not simply waiting for her to "get over this".... THAT is when reality sets in, and she possibly reaches her low.
Or... she simply choses him... freeing you to start your own path of healing.