If I try to quit, will the alcohol withdrawal symptoms kill me?

Possibly. Severe alcohol withdrawal sometimes called delerium tremens can cause death. The vast majority of people who stop drinking do not risk death however. If you have any concerns about your health when you stop drinking, consult your physician who can assist you in a plan for safely detoxifying from alcohol.
Sometimes. About 90% of people with alcohol withdrawal have "the shakes" - severe tremor, anxiety, sweating, insomnia, nausea, vomiting, diarrhea, but about 10% can go on to seizures, which sometimes can be fatal, or a severe illness called delirium tremens (dt's), in which people are agitated, confused, hallucinating, where heart attacks, strokes and death may occur. You should seek expert help.