Here’s what I did and what works.
Describe exactly the type of man that you think she’ll leave you for. You WILL find there’s a common characteristic.
When I was 25 and struggling in my career/wealth journey, I got EXTREMELY triggered any time there was a 32 year old man that was successful in his career. I realized I had a fear that my partner would leave me for someone more mature (less goofy) and more successful in my career.
What I realized from that was that I judged MYSELF for lacking those traits. Then I started to work on them. Now that I’m more mature (not being a goofball in conversations so much - but still have the ability to be playful) and more successful in my career, I don’t get jealous anymore.
Your jealousy isn’t about you not being able to trust other people. It’s you judging yourself, deciding you’re inadaquete in some area of life, and then playing this game of “how long before she figures out I’m XYZ and then leaves me for someone who has everything I lack?”
Try it