Meaning of "When in Rome!" by Eatmewhileimhot!

The lyrics of "When in Rome!" by Eatmewhileimhot! seem to describe a toxic relationship where the singer feels controlled and misled by the other person. The phrase "When in Rome, do as the romans do" is used to suggest adapting to a situation or environment, which in this context may imply the singer going along with harmful behaviors or actions of the other person. The lyric "You have a knack for bringing out the worst in me" suggests that the relationship brings out negative emotions and aspects of the singer's personality. The mention of being the first one to give away things they vowed to keep, the feeling of being constantly replaced and left behind, and the reference to being told to use your head more all imply a sense of betrayal, manipulation, and hurt. The decision to say "For sure, I'll never take you back" signifies the singer's resolve to move on and not allow themselves to be treated badly anymore.