We need to understand that we want what we want because we believe what we believe. In the Esau narrative, found in Genesis 25:29-34, we see that it was because of his wrong core beliefs, that he wanted the immediate gratification of the stew from Jacob. We would do well to carefully examine what we typically want during times that lead to bitterness. The challenge is that we are often so focused on the sins of others, we fail to examine the sin that resides in our own heart. We can rarely change the choices of those around us, but in the power of Christ we can definitely change the nature of what we want in any given situation. We often become bitter because our own heart wants things that are idolatrous replacements for right desires that would point us to satisfaction and joy in our Savior.