Relapse, properly understood, is a return to drinking after a period of recovery.
Do not mistake sobriety for recovery.
Periods of sobriety are part of the addiction cycle.
To drink, during part of the addiction cycle, is not to relapse but simply to progress to the next phase of the cycle.
The reason this is important is that, whilst the response to relapse is to return to the recovery programme that was abandoned prior to the relapse, if what is going on is not relapse but cycling through the drunk and sober phases of active addiction, the response is not to return to the sober phase of the active addiction cycle but to step out of the cycle altogether.