Could be friends in "companionate love" then.
Could keep the ideals of consummate love too and at the same time...could accept that you are not going to be sharing "consummate love" with EACH OTHER.
You are already in polyshipping and BF/GF to each other. And still don't feel better despite trying that approach for a while now.
So try the next thing. Break it up. Be only friends and behave only as friends do to each other. See if it eventually feels better. Rely on your companionate love to get you through the transition into a new relationship shape.
How does being unwilling to break up and try a new behavior help you stop going round in circles in this malaise?
Feelings ensue after behavior (even thinking behavior).
You keep choosing the same behavior and find it doesn't work and still feels yucky. Could change your way of going then. See if that feels better.
I know it is hard, but again... could choose to "unsuffer" rather than choose to continue to suffer.