When I interview women on this topic, they often say that what got them attracted to their boyfriend is his smile and radiance.
It is the fact that he looked happy, fun and outgoing.
That's a trait you DON'T want your boyfriend to lose! Believe me!
That's what brings joy to your relationship and makes it fun to be with him.
The moment you kill that, you destroy what you care for the most.
You need to manage your jealousy without destroying these qualities in him.
As a life partner, your job is to protect his freedom and happiness, not to destroy them!
So, how do you manage that specific tricky challenge?
You trust him and tell him what the TRUE boundary is.
The true boundary is: "Don't get intimate with another woman - If you do, I'm out"
That's usually the deal breaker in relationships.
95% of couples agree with this subtle and often unspoken agreement.
The other 5% of couples will have an open relationship or some higher degree of sexual freedom.
Listen, when he's happy and even flirty, what bothers you is not so much what happens there, it is the potential of what COULD follow up.
Women get jealous because they IMAGINE what COULD happen next.
Of course if you see him flirting with another girl, it might bother you a bit.
But what really gets to you is if they establish a connection that can lead to something else.
He needs to know what your EXACT boundary is:
"No intimacy with another woman"
Once he knows, give him space and trust him!