Yup, beware that trojan horse and any other purchases involving.... trojans ;-)

the EA is already taking place,
that's been my view from the beginning,
whenever a wife starts having this type of connection with another man, this is the beginning of an EA. They share interests, they enjoy talking to each other, they look forward to the next communication, communication becomes more regular with increasing frequency, they start planning things together, etc.

Ask the question, why isn't she like this with her husband?

She is sharing a side of her with another man,
she is communicating more with this other man than her own husband, an intimate connection is being fostered by this activity and the longer it continues, the stronger it will get.

They had a spat already with words being thrown about like "why don't you trust me?" (or something similar),
think about this, the relationship she has with this other man is so important at this point that she is willing to argue with her husband about this issue, the other man is too important to just let go of.