Hi friends!

I am 34F, married M40, been ENM a while, and have a couple of partners outside my marriage, including one long term partner 34M I see regularly. I would call it semi-romantic--we go on dates, and our sex is exciting and explosive. We have such a great time together, and I definitely have a crush on him, haha. We plan on keeping the relationship where it is--basically a friendship level of commitment/attachment, and that works great. I was having some difficulties with my anxious attachment style--you can read about it in my last post. I've been doing so much better with everyone's great advice...but then...

My partner confided to me that he has been dating someone monogamous for about 5 months! They see each other regularly and have even gone on a trip together! He has iterated to me again and again throughout our relationship that he can only be nonmonogamous, and I had the impression that he was dating openly ENM, so I was quite shocked! Apparently he has fallen for a younger, quite sexually inexperienced, woman who says she is monogamous...He hasn't told her about his (very heavy involvement) in the lifestyle and kinks...and he hopes he hopes he can "introduce her to the lifestyle"...essentially, change her. (yikes, right?)

I feel so let down! One, I feel a bit icky--I don't want to be the "other woman" to this young, naive girl who is bound to get her heart broken. Second, feel like his dirty secret. Its weird that I am having all this crazy, kinky sex with him, exchanging lude pics and finding sex parties to go to...and from what I understand, they are being slow and vanilla due to her inexperience. Third, I feel hurt and suddenly very insecure. Could he go exclusive? Drop me as soon as that gets serious?

Overall, it really sucks. I did like him a lot and had thought we were becoming close. I'm wondering what I should do...ride it out for a bit? Tell him about how uncomfortable I am with the situation? Run away!?

Any advice from some ENM vets would be helpful.