My mother treats us like children

So the other day my SO & I visited my mother for a friendly lunch. Everything was fine until we were finished with our meal & she confronted us with a need to talk to us. She went on this tirade on how our apartment is filthy and she feels offended coming there. For a little background: this is my apartment that my father bought me 5 years ago, unfortunately he passes 3 years ago... my mother is an obsessive cleaner & has a house cleaner at her home. We are both in our mid 30s... our home doesnt look like it came out of a catalogue but it surely isnt filthy, we live there and clean regularly, as much as our work load allows us to, & we always make a point of doing extra cleaning before we have guests. We were basically attacked, made to feel like we are irresponsible teenagers & my SO feels like she insinuated that he is poorly raised & dirty. I diplomatically thanked my mother for lunch & left, of course i told her that i feel offended by how bemeaningly she treated us. She has insane control issues and is known to boss everyone around. How would you react?