Sometimes moodiness is normal behavior. For sure, not all mood swings mean someone has bipolar disorder. If there is always something going on that can account for a person’s shifting mood, then it is likely that he or she doesn’t have bipolar.
When we have genuine Faith in Father God, we won’t act like human beings are in control of the circumstances, letdowns, struggles, setbacks, washouts, and so on, that come our way. When we have genuine Faith in Father God, we won’t be afraid to show happiness when we are happy, and sadness when we are sad, and etc. Lastly, when we have genuine Faith in Father God, we know how to take things as they come—we know how to be truly “content” (to no longer be disturbed or disquieted by anything that happens to us in this world, because we faithfully trust in the finished work of Christ Jesus). As a result, we will have no need to be plastic Christians on the road to becoming problem children with disruptive, ungodly behaviors.