Hi, Mountaintom!
Yes, I used to meet a good counsellor at the diabetes clinic but it was a long time ago and it was not exactly all about diabetes (when I was dxd I was struggling with a difficult situation at home, I was very young and my mom had taken to drinking and things weren't good in so many ways…). She was an expert in T1, though, and that was a great advantage.
Recently I've been trying to find a good counsellor again, but there seem to be no T1 expert available any more… not in my place at least. But you could be more lucky where you live!
Perhaps try and visit a website called 'Beyond Type one': you will find a post about professional counsellors who are T1 experts as well, that might be useful. Unfortunately I don't live in an English speaking country and we don't have many such professionals, but I hope you will find one. Of course it's just my personal opinion, but I think it makes things easier if you can talk with someone who already knows quite well about living with T1: it saves times, for one thing, and will help you feel better understood, as a whole.
Best wishes!