Polymeric materials and composites are essential in modern engineering, yet they generally exhibit lower mechanical strength than metals and ceramics, making them susceptible to damage such as microcracks, which are challenging to detect and repair. Inspired by nature’s ability to self-repair, researchers have developed self-healing materials that mimic these biological repair mechanisms. These are typically classified as extrinsic and intrinsic systems. Extrinsic systems use embedded healing agents that are released upon damage, but healing occurs only once, and efficiency decreases as agents are consumed. Intrinsic systems, like vitrimers, can repair repeatedly due to dynamic covalent bond exchange, making them ideal for sustainable materials that reduce waste and extend lifespan. Despite progress, computational modelling of self-healing behaviour remains challenging. This study introduces a novel model to predict the isotropic damage and healing behaviours of self-healing epoxy vitrimers. Based on thermodynamic principles, the model employs two internal variables: mechanical damage (d) and healing (h), with healing modelled as reverse damage, and with the assumption that damage and healing do not occur simultaneously. An effective damage variable (d_eff) captures the interaction between degradation and healing. Damage evolution is activated by a force derived from the system’s free energy. The model’s key innovation is the treatment of the healing rate, which follows an Arrhenius-type expression driven by thermally activated bond reorganization. A custom MATLAB implementation at the Gauss point level verified the model’s accuracy in capturing key vitrimer behaviours. Future work will validate the model with experimental data, extend it to handle simultaneous damage and healing, include pressure forces, and explore multiple healing cycles. These developments will enhance the model’s predictive capabilities for applications where material durability and sustainability are essential.