Spouses still cannot be compelled to testify against each other but, at least in federal court, they are permitted to testify against each other. So the moral is don't get your spouse mad enough at you that s/he will waive the privilege.
Also, there isn't (and never was) a privilege for people who live together but aren't legally married. This defendant was convicted of injuring a girlfriend, not a wife.
What I’m getting at here is the High Court is creating another “special relationship” for the purpose of claiming the power to assign our rights. If assault is bad, then assault is bad.
Why does it become special if it involves a “domestic relationship”? Find that clause in the constitution. This is not different from gay marriage or government finance of abortion.
Just because it “feels right” seems to be the judicial standard.