What kind of aggressive/hostile feelings are activated in your therapy
sessions? What seems to trigger them? Have you discussed this process with your therapist? This is a legitimate topic for your therapy and your therapist should be able to help you with it without withdrawing needed support from you.
One last word: Your therapist is legally required to warn potential victims and, in some cases, to notify law enforcement officials if s/he reasonably believes that you are likely to harm yourself or another person. In such a case, your therapist is permitted to break the confidential relationship between the two of you in the interests of protecting both you and your intended victim. For this reason, as well as his/her interest in your continued growth and well-being, your therapist is not able to support or condone violent actions under any circumstances.