Help..15years

My boyfriend and I have been together off and on since high school..15 years! He was my first, my first love, my comfort, my go back to guy, my everything. I mean he still is, but his anger is something that's blocking me.
Last night we got into it. We were out with friends and my bf dropped a beer can outside a store. His friend nonchalantly went to the cooler and just grabbed a replacement and didn't pay for it. I brought this up after we left because the store was in the building of the company I work for and I didn't wanna be associated to a steal.
It all started from that!! He didn't like that I brought it up after he had such a good night with his friends and started yelling and calling me names that I hate with a passion. Then..something triggered and he punched my rear view off my windshield! Then more fighting a yelling and then started punching my windshield!!! As he was doing all of this he said "he wants to just kill both of us" as he was driving me home!!!!!!! I shut up so I wouldn't trigger anything to make him more mad, but I really wanted to call the police.
This has never happened in the 15 years but once is enough for me..so I honestly don't know what to do. Sounds simple, but I love him with all of my heart and can't imagine my life without him. But love my life more than him.
Please help..I need someone to talk to with a mutual ground.