Col Brandon thoughtful hunk! ;D Col Brandon may be grave and silent on occasion but he always exerts himself to be attentive to others and when he speaks it is with sincerity IMO. Lady Middleton’s coldness (inattention) is specifically stated to be towards her husband, mother, and the rest of the world with only her children being the exception so it is unsurprising that she enjoys talking about her children and watching them exhibit is probably delightful to her but that does not mean she is being attentive to other people while doing so. Talking only of your favorite subject tends to ware on people and make them think you are uninterested in them and I think that if done too often people might believe that person is without sufficient resources. ;D

I think you are right that Lady Middleton and the Dashwoods do not have enough in common to base interesting conservation on but in her position as hostess LM should exert herself to be attentive to her guests regardless of whether she finds them interesting or not but other than that if she is silent I do not find it worth censuring. I do not see LM outside her duties as a hostess being burdened with entertaining the rest of the world and luckily for her Sir John takes up the slack left by her inattention. LOL to the idea that LM may be fed up with partying and I think she would have no say in the matter—IMO Sir John would forge ahead with his plans despite any wish of hers to the contrary. My main point above is that what is perceived as coldness by the Dashwood’s is not a result of circumstance (absorption in her children) but of character (not interested)—IMO of course. ;D