Hate seeing my mom unhappy

My moms been Married to her husband for 8 years. He works and pays all the bills on time, doesn't cheat or abuse my mom, But he drinks every single night until he's drunk off his ass. He will have a 30 pack in the fridge and STILL buys more beer just to stock up on. Every single night he gets so drunk he passes out. It gets so bad sometimes he will pee random places not even knowing what he's doing. My mom has told him time after time she doesn't like that, because it's hard to even enjoy your "husband" when he's drunk every single night. Sometimes my mom wants affection and wants to cuddle and enjoy eachother and he can't even do that. This has been an issue for YEARS now, and he won't change or take her feelings into consideration at all. He's an alcoholic.

Also, he lets his 20 year old son live with them and doesn't make him pay bills, clean the house, etc, his son is so dirty and all he does is play video games ALL DAY.

My mom feels like she's gotten to her breaking point between those two things.

And I totally see why she feels like that.

Would that be enough to leave someone to you?