I am not an expert. I'm a guy who has successfully navigated several jealousy crises on my NM journey.

TLDR: Fix your current panic first. Do this with body work. Then, focus on reducing shame and loneliness. Do this by increasing feelings of acceptance (self and others) and by building emotional connections with other people. DMs are open if you want to talk.

I see a lot of posts on here from people experiencing a jealousy crisis. Maybe it's the first time your partner is seeing someone else, or maybe you're just having a really bad day. If you're here, it's because you are reaching out for connection and support. That's good. This community has helped me countless times. Read the books, listen to the podcasts, return to the comments and stories and DMs you get. I did, and it helped a lot.

Here's some of the ideas and practices that helped me the most.

1. If you're in crisis right now, you need to address that first. Tingly skin, short breaths, sour stomach? Your body is panicking. It thinks that your life is in danger. That feeling is valid and normal. But it's also preventing you from doing the things that will keep you safe from danger. Your body is in control right now. It's making your mind race. It's making you imagine your partner with someone else, or leaving you, or lying to you, or past times that someone else did those things. You can't calm your mind while your body is in control. You have to start with your body.
   • If you have any sort of regular practice with your body, do that thing right now. Still panicking? Do it again.
   • Body Work examples: meditation, weight lifting, breathing exercises, nature walks, stretching, folding laundry. Anything that puts you in your body.
   • If you don't know where to start, pick one of these: go for a walk, or close your eyes and try to take 16-second deep breaths (4 in, 4 hold, 4 out, 4 empty).
   • As long as your body thinks you're in mortal danger, you aren't ready for the rest of this. Don't rush it. You won't get to full-calm right now, but you should be able to get yourself out of full-panic.
     
2. Where did that panic come from? Why did your body feel like your life was in danger? Learning about this process and accepting that it's a valid reaction helped me reduce its impact over time.
   • A single human can't survive on its own. We need caregivers when we're young. We need partners, friends, and caregivers as adults as well. Your instincts know this. You have reflexes built into you, triggers that watch out for Social Threats. When that threat is detected, it causes the same reaction as seeing a tiger in the bushes. Your life is in danger. That feeling is valid and normal.
   • But you aren't about to get exiled from the village. You aren't really at risk of being entirely alone in the wilderness. So why does it feel that way? It's because you have created a strong attachment to a single person. Your partner is just as important to you as parents are to a small child. A threat to that bond feels like a threat to your life, even though it isn't.
   • If you're just starting to move from monogamy to non-monogamy, this threat reflex is probably really powerful. You have built this one attachment up to be so strong that any threat to it is more powerful than an actual threat of exile from every other relationship in your life.
3. Try to understand Jealousy as a whole system of perception, interpretation, and response.
   • When I say Jealousy going forward, it's this process that I'm talking about. Perceiving a threat to a critical social bond triggers the reflex that is watching for signs of exile, and it makes your body feel like your life is in danger.
   • Turning up the sensitivity means you will perceive more threats, have them trigger more reflexes, and have a stronger physical response. A very jealous person will perceive dozens of potential threats in everything their partner does: "a man told a joke, and she laughed at it." The jealous person will imagine each potential threat as more dangerous: "women like men who are funny, so she might leave me for him." Lastly, the jealous person will have a stronger emotional reaction to those threats: "I have to grab her arm and get her out of here right now."
   • Turning down the sensitivity means that you will perceive fewer threats, view them as less dangerous, and have a more measured emotional response, even when the threat is real. A less jealous person can still identify real threats: "he said he loves someone else." They can assess the context: "he loves me too, and she has other partners she loves." They have an emotional response, but it's one that is more helpful than damaging: "I should make time to talk this through with him and tell him how it makes me feel. I need some comfort and reassurance."
4. Loneliness and Shame turn the sensitivity of this system up. Connection and Acceptance turn the sensitivity down. Both of these are self-reinforcing processes. People who are very jealous will alienate people and start to hate themselves. People who are less jealous find it easy to build strong relationships which makes them feel loved and accepted.
   • Loneliness amplifies jealousy because the fewer meaningful connections you have, the closer you are to true exile. If your only meaningful connection is to your romantic partner, that should be a giant red flag about your life in general. Do not attempt non-monogamy until you have a better network of connections.
   • Shame amplifies jealousy because it's a sense that your feelings or behaviors are not what they should be. This is a warning sign that you are out of step with the expectations of your society, which in turn means they might suddenly turn on you.
   • Building meaningful relationships with friends, family, neighbors, and romantic partners will help you feel secure. Losing one relationship, even a primary one, will not mean exile. Other people will embrace you and help you through it.
   • Feeling true acceptance from yourself and others lets you know that you have some leeway to screw up sometimes. They aren't going to turn on you without warning. One little mistake won't cost you everything. You will know that you are good enough as you are. People see the real you, and they love that person. You have a stable foundation for growth and change.

This is just one way of thinking about this stuff. It's a framework that has been very helpful for me. I have cobbled it together from many resources I found through this online community and from my friends who have been through this before. If you think I'm saying something harmful, please say so.

My DMs are open if you want to chat. Good luck on your journey.