Pregnant and husband turned to drugs

I'm 23 weeks pregnant and my husband came back from a work party at 10pm tonight. I knew he was drunk because of the smell of alcohol and he always gets impulsive and angry with alcohol. But this time he took it a whole other level and it has to be because he is on drugs. I am thinking LSD. He said he didn't know who I was and started making up weird conversations about where is his wife (me), and started screaming at me asking who I was and he wanted to kill me. He gets drunk and nasty but never to the point that he doesn't know who I am. His coworkers do acid and are usually happy calm people but that doesn't make it OK to do such drugs. Due to his alcoholism and lies I should have left him a while ago. But now that he mixed acid and alcohol I have to leave him for the safety of my baby and myself. I just wanted to come on here and ask if you ever been through alchoholism/drug addiction or knew anybody in your family that had this issue. How did you handle it? Did you leave or send them to rehab?