It is impossible to say for certain what would have happened to the mother if the speaker had not left. However, it is possible to speculate that the mother may have been in danger if the speaker had stayed. For example, the mother may have been physically or emotionally abused by the speaker, or the speaker may have been a threat to the mother in some other way. Additionally, the mother may have been unable to get the help she needed if the speaker had stayed, such as if the speaker was preventing her from leaving the house or contacting others. Ultimately, it is impossible to know for sure what would have happened to the mother if the speaker had not left, but it is possible that the mother may have been in danger if the speaker had stayed.