"Worst In Me" by Julia Michaels explores the complex dynamics of a troubled relationship where both partners struggle to confront their negative traits and work on the issues that arise between them.

The song begins with a reminiscence of happier times when the narrator and their partner were supportive of each other's interests and successes. However, as time passes, they both become afraid of the potential for the relationship to actually succeed. They are aware that they could make it work, but something inside them resists the idea.

The chorus suggests that there is a darker side to their personalities. The worst in the narrator brings out the worst in their partner, creating conflict and preventing them from growing together. The narrator yearns to fix the problems between them, but their own flaws and insecurities hinder their ability to put in the necessary effort.

In the second verse, the narrator expresses how resentment has built up over time, making them less responsive to their partner's needs and more dismissive of their words. This resentment has also had an effect on the partner, making them bitter when the narrator doesn't react as expected.

The bridge serves as a plea from the narrator to their partner, expressing a desire to avoid hurting them again and a fear of losing them. The repetition of the line "Remember when I used to be happy for you?" highlights the contrast between their present state and the past when they were genuinely supportive.

Ultimately, "Worst In Me" describes the internal struggle faced by the narrator and their partner in trying to overcome their negative tendencies and work on their relationship. It confronts the fear of vulnerability and the challenge of personal growth within a troubled romantic connection.