In recent years, mechanochemistry has imposed itself as a novel promising chemical tool to bridge the gap between polymer physics and continuum mechanics in soft materials. The suitable incorporation of force-sensitive molecules (mechanophores) in load-bearing positions in soft (entropic) polymer networks provided a tool to detect stresses and bond scission in 2D and 3D through the intensity of an optical signal. We will discuss some recent results linking the optical signal detected upon mechanophore activation with the applied mechanical load. Recent investigations have addressed questions, such as detecting and quantifying stress fields in soft materials and measuring quantitative damage by bond scission. This could be achieved in diverse mechanical loading situations such as failure in uniaxial tension, crack propagation during continuous loading or due to cyclic fatigue, or crack initiation in uniaxial or triaxial tension. In ideal cases, the optical signal provides highly sensitive quantitative detection, enabling comparisons between different materials on the size and intensity of molecular damage zones that would otherwise be undetectable.