He’s assaulted you criminally twice, possibly 3 times. You could have reported him to the police.
You could have a job that requires drug testing, be pregnant (I mean, I guess if you were drinking that’s a bit far fetched but still), in recovery… there are many reasons it could have been awful for you not least just saying no, you don’t want to.
If he’s not just a drunk wick and this is a pattern of behaviour then he’s a dangerous individual who may be jealous of your relationship and would be happy to isolate her to gain more control. Sadly though you can’t be collateral damage. I’d tell him, not even your friend but him, if he so much as lays a hand on you again you’ll report him. If your friend can’t deal with that then it’s likely he’s controlling her. If it puts a wedge between the two of you I’d explain you love her but you can’t allow yourself to be around that kind of behaviour, you’ll always be there for, no matter what, no matter when and try to keep an eye on her so far as is possible.