Curve offset to nothing?

I have a curve that i’m offsetting in the negative direction (i.e., to get smaller)…the offset works up to a certain point (image 1), however at a certain offset distance just beyond the bounds of the original surface, the offset starts to “recreate itself” in a chaotic geometry (image 2). My goal is to have the curve just NOT offset itself if it gets to that point…any insight as to how I can do that?

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