This is more of are we the asshole. Me and my wife have been married for 2 years she has 3 sisters all of which we care about a lot. This is about her older sister Maira (28). Currently in a relationship with a guy named Erik (32). Both work in finance and make good money, while he is a little better off in the money department. Now from the beginning when I first met this guy I didn't get a great vibe from him. For one he was way to nice and another he was a certified platinum ass kisser to my wife's parents. I just remember telling my wife "there is something wrong with this dude." She would be against me of course and say I needed to give him a chance and hang out with them which I agreed to, and we made it work. 

Until about 6 months into their relationship my wife gets a call from her sister saying that Erik wants nuts. Apparently he went ape shit on his house and tore a door down and ripped a faucet out the sink. All this came from a message from a co worker my sis in law recieved. Started calling her a lying bitch. Slut. Yata yata. Demanded to know everyone she had ever dated and if she still speaks to them. All this with his nephew in the house. Apparently they move on from this until about 2 weeks later. When my wife gets a call in the middle of the night from some random stranger saying that he has Maria in the car with him asking if we could pick her up. What happened that night angers me to the core because I don't condone that type of shit. That night they were drinking and had one to many. Got home and she was chatting with some co workers through text. He got angry because he thought it was a dude. This led to him hitting her, smashing her phone, and taking her car keys so she wouldn't leave. She ended up running away from his house barefoot, in her underwear and a tshirt. Luckily the random stranger was a great guy who picked her up and asked if she needed help. 

After we get her home, she goes back to his house the very next day. Like nothing happened. Her parents found out about it and act like nothing happened. Say she should work it out with him and go to counseling. I for the life of me can't comprehend this. Me and my wife think she should get out of it, and it makes us look like bad guys because we try to avoid him at family functions. My wife's parents get angry at us for this and it makes us look like assholes to her family. No one else knows except us 4. Are we assholes?