Thank you all so much for your support, challenges and insights. I feel like posting a little update.
I spoke to the friend involved a week ago and we cleared the air; she admitted to me that she was not acting in her highest integrity, which was more than i expected or needed to hear but really helped me let go of the fact that they didnt communicate with me until afterwards. I feel incredibly free after releasing all that frustration and jealousy - Real Ease. It is good to have my sister back, for the most part.
Most exciting, I have shared a wonderful connection with a close mutual friend of my partner and I, who is an open and loving creature who has been honest with the both of us about his attraction to us. Even my partner, not used to exploring with other males, is very curious about this connection, although he is currently struggling with jealousy (it didnt really occur to him until recently that i might actually start playing with other people). The last few days this friend and I have taken new steps in our appreciation of eachother, and I am opening myself to the world with a billion new possibilities and discovering more about myself. Sexual and romantic play is very new to me other than with my partner, so this has been challenging and enlightening. Our time together is very grounding and incredibly aware, which is in great contrast to my current relationship with my partner, even though we love eachother more and more each time we meet now.
I am practicing unconditional love towards everyone I come across, and the more I do this the more the universe gifts me incredible bounties....
I'm so grateful for the support of you lovelies in this forum. It's quite an interesting journey I'm embarking on, and I'm incredibly excited!!! Blessings