Break up with your boyfriend.
You’re only 26 years old, time to leave! There are so many red flags around this. 1. Your bf is hanging around a guy doing coke all the time it’s likely he’s partaking aswell. 2. He thinks that a woman who throws water on her bf to wake him up from a coke binge deserves to be beaten by him, does that mean he’s going to do the same to you? 3. After all of this what other unsavoury things do they get upto when their together?
No, no, no, dear. No one deserves that. Your boyfriend justifying it is as big of a red flag as it can get.