Certainly if he is deploying in two weeks and not talking about D right now, then there isn't much to lose by just laying low. OW won't be waiting around for him like you will.
You were wondering what makes EA so interesting. OW is doing nothing but validating whatever he thinks, and probably sharing her problems with him. Like a therapist you can flirt with. He should be sharing his problems with you, but what if you are the problem? And it is so easy to be understanding for a few hours a week.
BTW, my EA was with a married woman having trouble in her marriage. Very typical. But once I was available, suddenly she wanted to back off from me and work on her marriage. As a single man I was too much of a threat to her marriage. Its all fantasy.
