primary loan holder is purposefully not paying student loans

I cosigned a loan for my ex when we were together. We have since split up and because of the breakup she is purposefully refusing to pay the loans. Im aware as a cosigner im responsible for the loans however due to the fact that I have saved text messages of her stating shes not paying them and intentionally doing this to hurt me and my credit score is there any legal action I can take to protect myself?