"Do you think I'm being stupid still sleeping with my W in this situation? "
I don't think it's stupid. I think it's just naive. So she's still seeing the OM (her choice) and having sex with you (you initiate and she doesn't). The logic sounds messed up.
It sounds like she has sex with you to keep you off her back. Emotions are more important to women than the physical attraction. If she is emotionally tied to this OM, it doesn't matter if she has sex with him or not. The connection between them will continue to grow while you're left with sloppy seconds. She's going to determine when she's done with you.
Is that what you want?
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.