Deep discharge due to defective warning flash switch V40 1,8 ltr Bj 1998

The warning flash switch is a component of this series, which doesn’t exactly shine with fitness. Replaced a few years ago by a new one, because the snap mechanism didn’t work anymore. Well, just a few days ago the fucking switch – and you hear and marvel – made itself independent after setting off, flashed all night in front of it and in the morning the battery was empty, so empty that not even the locking system worked. After charging the battery, goes the turn signal only with permanent light. I assume that the turn signal relay was also worn out. Has anyone ever done this before? Or does anyone know about it?