"I broke Suzuki ... Nevertheless, in an effort to protect you,
The second sentence, who does it refer to?
Context: A girl (Lisa) says those lines to her boyfriend. Previously she had been talking with his exgirlfriend (Susuki), who had entered into a deep depression because the boy had chosen Lisa. Lisa tries to confort Suzuki but ends up hurting her more. At the same time Lisa was worried because Suzuki kept saying that she will win him back, to which Lisa says that she will always be with the boy, so that's impossible.
My question: In the sencond sentence who was Lisa protecting? The boy (making it clear he's hers) or Susuki (who she wanted to console and make amends with her). She's talking to the boy when she says that.
If you have a better translation of the paragraph I would also appreciate it.