Cull lines after proximity 3d

I was wondering if there is a way to cull the lines that are between the curves. I used proximity 3d to get the lines but since the distances between the point change, it was
snot enough to remove everything (the ones highlighted for example), is there anyway to get that? maybe make solids from the curves and test for inclusion of the middle point of the lines? Thanks (42.2 KB)

Maybe something like this: (41.5 KB)

Thanks for the quick reply, that is actually one way to do it, however projecting curves to the plane will not be accurate if the curve had placement (I attached a file with more curves for reference).
proximity_v2 (238.6 KB)

Here is another option.
proximity_v3 (453.1 KB)
I am not sure where your curves are coming from, but they are a little messy. I had to clean them up a little manually to get this to work. I guess there should be a way to clean this earlier in process, but without that part of your GH definition, its hard to say.

Thanks, yeah I had to clean the curves by hand before applying any further steps, but it works thank you.