I am a secondary mainstream SENDCo, have been in role approx 18 months.
Our provision is, I think, excellent. There are myriad opportunities to communicate provision with parents, which we do effectively. Most parents are fairly happy with their child’s provision.
A handful of parents just take up all of my time. No matter how many times I sit and listen to their concerns, validate them, agree with them, point to the provision in place, suggest extra provision, make them feel important, they just cannot get their head around the fact that their child does not have a 1:1 TA.
I am smiley, concerned, lend them an ear, offer a range of options, and I am constantly ignored, belittled, huffed at. Yet I keep smiling and being helpful 
Secondary SENDCos, how do you handle these meetings, emails and interactions? Please help me before I quit in high dudgeon!