I feel like it's a little more nuanced than that, to be honest. I think the Bully girl likes bullying people(since she seems like she's enjoying herself on the top left of page 2), but she also hates that she does it(as seen with how regretful she looks and how she starts crying at the end). I think it's rather similar to someone who has a terrible addiction(like gambling, smoking, cheating, etc) that feels really good when their in the act, but they always feel regretful when it's over.
It's like a "I know this is bad, but I just can't stop" kinda thing, and I feel like the dialogue proves this with phrases like, "her love is so warped// and hopelessly clumsy" and the fact that the protagonist girl sees this side of the Bully Girl as a part of who she is. I still don't think it's healthy, though