3 switches for 2 lights split into 2 switches per light

We have a center-entry hall way with a light at each end. There are three 3-way switches. One in the middle, and one at each end. All three switches control both lights at the same time. We want to split the center switch into two so that the switches at each end and one of the center switches control ONLY the light for that end of the hallway.

Switch A—-Light 1—–Switch B—-Light 2—- Switch C is what we have.

Switch A—-Light 1—-Switch B / Switch D—-Light 2—-Switch C is what we want.

How do we split Switch B into B & D?