You NEED professional help.
Even if you're afraid you might do something stupid while with a therapist, you still need to go try. They're trained to deal with those types of situations, so the best thing you can do is tell him/her up front that you're afraid of getting violent during sessions.
This seems like way too big of a problem for you to deal with on your own, so you really should seek someone out. Your alcohol dependency will only exacerabte your anger issues, so it's extremely important that you begin to wean yourself away from that dependency. Groups like AA have good reputations, but i haven't ever gone to any of them, so I can't reccomend it first hand.
Before anything, however, definitely make youself go to a therapist. If you're already physically lashing out at people, especially those you care about, then you need help immediately.