A return to use does not erase the work you have done. Addiction behaves like other chronic conditions. It can flare up, especially under stress or after a change in routine, and that flare tells you something practical. It shows what your treatment plan was missing, not what kind of person you are. What you do in the next day or two counts more than the slip itself. Reach out, be honest about what happened, and get back into support before the shame builds.