My relationship is eroding.

My wife and mother have not gotten along for months now, and my mother has tried to move past it, and my wife is steadfast in that she cannot.

Rewind when it escalated. My wife had gotten snappy toward my mom, and that was kinda the end of it, so I thought. A few weeks later my mom said some choice words toward my wife, and she rightfully felt disrespected.

8 months later(today) my wife is still unwilling to show me much or any affection so I confronted her about it.

Her response was that she does not feel like I will protect her against verbal attacks from anyone(nothing has happened since), and the fact that I still speak to my mother disgusts her... We rarely have any intimacy, sexual or otherwise, and if I bring this up she tells me to just suck it up or cut my mom out of my life.