I've been a practicing Buddhist for a little over a year now, in the tradition of Thich Nhat Hanh, in a very non-dogmatic and westernized Sangha.
It was learning to care for my suffering, and to look deeply at the roots of my suffering, that led me out of jealousy (which I came to recognize as fear), and allowed my husband and I to start the poly conversation.
I was so interested in finding this thread here, even though it is old now. My Sangha practices the version of the five mindfulness trainings that commits us to sex only in the bounds of a monogamous and public relationship. I pretty much vocalize against this every time we study them
And I have found that despite that, the only people I can talk to about nontraditional sexual and romantic relationships are in my Sangha. I'm so grateful for this practical application of loving kindness and deep listening!