Have you asked him why he wants you to die? He might be trying to protect the body/you, or he might be upset with not having his concerns taken seriously. In my experience, alters were usually created in order to protect the person/body, they just don't have a lot of skills to deal with regular life. Another issue I've come across is that when an alter is angry it usually has to do with them needing something, and not having their needs heard, validated, and/or dealt with. Trying to understand them, and acknowledge that they are trying to help me in their own way has helped many times when my alters have been angry.
Not that this will work in all cases, but it would help if you knew all of the "WHY's", so that you can understand where this is coming from, etc.
Best,
IJ