The opposite of re-united would be 'disunited.' Disunited means the opposite of being united or coming together for a common cause or goal. It encompasses a scenario where people are separated or disconnected from each other, where relationships are strained, and communication is broken. Disunited often leads to a breakdown in trust, collaboration, and mutual respect. In extreme cases, disunity can translate into conflicts, enmity, and even war. Thus, it is essential to recognize the value of being united and strive to maintain harmonious relationships with those around us to avoid disunity.