Being a source of strength means being supportive, reassuring, and empowering. However, there are antonyms to this phrase, that could denote various things. One of those antonyms is being a source of weakness, which means being a negative influence or a person who demoralizes others' spirits. Another antonym could be being a burden to someone, which indicates a person who is demanding, clingy, or dependent on others. Moreover, another antonym could be being a source of distress, indicating a person who brings anxiety, frustration, or sadness to others. In conclusion, it is crucial to be aware of the different antonyms of being a source of strength to ensure that one does not engage in such negative behaviors.