Violence solves nothing...let me repeat violence SOLVES N-O-T-H-I-N-G. Step in, if they can not resolve their matter like civil adults
1. maybe they shouldn't be together, much less married
2. they are intoxicated and should be stopped regardless
3. they are really REALLY angry at each other and is best to have some time apart to cool down and talk civilly
Either way break the fight up some way all it takes is ONE punch to land in the wrong spot to have a disfigured face, broken bones, or worse brain damage. So yeah step in.