Thanks for the reply Perna. Funnily enough, I've tried exactly some of the things you've suggested, with mixed results.

There's just no dealing with him rationally though. It's like everything he does is designed to dominate, confuse and undermine - so sometimes in the middle of discussing something he'll hang up the phone or say stuff like - "none of that made any sense - you're mad" after I've spoken to him calmly about how I'm feeling. The other extreme is I react with anger and then of course, I'm mad again and he says he's told his partner about me and she thinks it's disgusting etc. So then I say ok, just leave me alone, don't contact me at all and then he complains about that - There' no winning really, which is the point of his behaviour I think - it's all a childish game to him but one he rigs in his favour - One cricket analogy I use a lot lately when discussing him is that "he's not playing with a straight bat". So to continue the analogy, I'm going to stop bowling and leave the pitch

Anyway, I'll find a way - I think the sarcasm suggestion is a good one. Sarcasm is a way of hiding genuine emotion and distancing my "raw" emotions from being exposed (something I think he thrives on) so in a way it's a perfect balance between being too sincere and getting angry. I'll give it a go and see if it calms things. Eventually he'll give up if he realises he's not getting an emotional reaction.

As for counselling, work have a free service so I may make the most of it if I need to. Feeling calmer today so hopefully I can let this blow over or start dealing with things differently from now on.