} else {
			// decrement the destination edge index on this neighbor if the edge between us was a destination edge
			edgesToRemoveFromIndexes = append(edgesToRemoveFromIndexes, g.graph.EdgeBetween(vertex, neighbor))
		}
		return true
	})

	// remove the vertex
	g.removeVertex_locked(vertex)

	// remove neighbors that are now edgeless
	for _, neighbor := range neighborsToRemove {