Modeling a complex structure

The structure I'm modeling is very complex. it's a double layer structure with one wrapped outside the other. The structure is on nanoscale, so the mesh has to be really really fine.

Due to the complexity of the structure, it is very difficult to mesh it or compute. If A coarse mesh is chosen, it often ends up failing to mesh the geometry. If a fine mesh is chosen, the memory runs out fast.

Is there any solution to this? Thanks.