For me time and reassurance was exactly what I needed, but I know for some people, time just causes a festering wound.
What really helped me was for Karma to tell me why he chose me. Why he chose to stay with me and her instead of leaving me for her. I needed to hear why I was special, why I was different.
I felt that I obviously wasn't enough, why else would he need someone else? I have poly leanings, but was able to commit fully to Karma. He ws enough for me, that's why I married him, so why wasn't I for him?
It took me really thinking about things to understand that the I accepted the more I came to know myself.
And honestly, the biggest help for me, was to have a long time crush persue me. At a party on night we kissed quite a few times, and he told me that it was my marriage that stood in the way of us.
I left that night thinking why? Why does it have to? And then the light switch turned on. I guess I needed to have feeling for someone else awoken in order to see where Karma was coming from.
He is my other half. He is enough. Adding someone else just makes it better.
I'm a pastry chef so I do food analogies a lot.
I love warm apple pie. I love vanila ice cream. Warm apple pie with vanila ice cream is heaven. I can have one without the other and be completely satisfied, but when I can have both I experience multiple textures, temperatures, flavors, mouth feel, they enhance eachother.
I'm Karmas apple pie and Cricket is his ice cream. Our marriage has had so many positives because of his relationship with her. New perspectives, new awareness, much better communication.
Keep that open line of communication. Encourage your husband to express his feelings without being made to feel bad.
One thing that really helped me was that Karma NEVER made me feel like I was wrong for how I felt. He got frustrated in not knowing how to help, he hurt b/c I hurt, but I never felt that I couldn't tell him how I felt and have it respected.
It took us a lot of talking, a few tears, some insecurities, some anger, some feeling left out, but we're so much better for it.
It sounds like you are being respectful of him, so good for you, keep at it. Ask him what he needs and try your best to provide that.