My situation had several similarities to yours. A few thoughts for you. First, regarding "getting played," I understand why that would be a source of anger for you. In reality it's usually not that black and white. I would be that your W really didn't believe she was over the line for a long time, and therefore she wasn't "playing you" because she truly felt her actions were fine. People who cheat usually don't just get a wild hair up their arse and decide to go a-cheatin', it's usually the result of thousands of micro-escalations, none of which are carefully considered, then they suddenly find themselves over the line.
Doesn't make it right, doesn't make it acceptable, but it's usually not as clear cut as "getting played".
Regarding my W, what she really got addicted to was the attention , the excitement of the shared secrecy, and the romance. These things were far more important than the person, and those feelings are truly addictive. I mean really, who wouldn't want to be the subject of admiration and attention from a member of the opposite sex? Of course that feels good. If you can keep that going over a long period of time it becomes your norm and something you feel you "need".
In reality that's not normal at all. Real relationships don't have extended periods of one-sided positive affirmation, real life gets in the way and relationships establish an equilibrium that really isn't all that exciting. It can be good or even great, but it's not exciting like a new romance for years on end!
When I got to where you are now with my W, I was relieved because I thought that OM being gone and NC being established meant that the threat to the marriage was over.
Although that guy did disappear and they did honor NC, my W went through a very real grieving process about the loss of those feelings, and subconsciously blamed me for it because I had "taken that away from her" and not replaced it, because she didn't feel the same way about me. I couldn't replace those feelings because she didn't want me to, nor could I, because our relationship was reality, not fantasy.
In any case, I took a real shot at reconciliation over the course of three years, but unfortunately, W never got over the void that was created in pursuing these exciting feelings, so she just started the cycle again with someone new. At that point I'd had it and we got divorced.
Believe me, now her life is very "real world" as dating in your 50's "for real" bears no similarities to having the security and stability of marriage plus pursuing excitement on the side. That option is no longer available to her, so she's needed to get over it because she hasn't had another choice.
The bottom line here is that making sure she's done with OM is only a small part of the process. She needs to grieve the loss of these feelings she got from their interactions, realize that those were not a realistic expectation for a long term marriage, and change her life to learn to live without them, without constantly seeking opportunities to get them again.
If she doesn't do that hard work on herself, the cycle *will* repeat, either with the same OM or with a new one. It's not about the guy, it's about how she feels about herself due to the attentions of the guy. She needs to learn to feel good about herself without that, and that's not something you can do for her.
Acc
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015