There are various alternatives to "from this moment on," depending on the context and intention of the speaker. Some possible synonyms include "starting now," "henceforth," "hereafter," "from now on," "as of this moment," "beginning today," "in the future," "henceforward," and "going forward." These phrases all convey the idea that a significant change or decision has been made and that the speaker is committing to a new course of action or perspective. They can apply to personal or professional situations, such as a new job, a resolution to quit a bad habit, or a vow to express more gratitude in relationships.