I have not ever felt jealous in relationships I have been in. However, I also have never been in a polyamorous relationship, so it is hard for me to tell how I will feel when ouroboros gets romantically or sexually involved with someone else.
What I think about is how love is freeing... for yourself and for the person whom you have feelings for. I think about how I would want to be treated and how I would want someone else to feel for me and show this through supporting me in my endeavors so long as they are healthy and beneficial to my life and thiers. Then I try to treat them in this way...
It is easier said than done, that is for sure!!!