Stoic sources actually state explicitly that Stoic ethics is all about preventing "self-harming behavior" arising from our emotions. They just have a much more expansive definition of what's "self-harming" than modern society does! Raw emotional responses are seen as mere facts of nature that cannot be meaningfully avoided and repressed, but they can still be subjected to reasonable judgment, and then accepted or critiqued. The common modern idea that Stoicism is merely about emotional repression and a totally "unemotional" stance is quite a misconception.