I work with a man who has ADHD. This week he berated me in front of a customer, to the extent that the customer got involved in calling him out on his behaviour. This has been an ongoing issue for 2 years, he is argumentative, belligerent and controlling. He is my equal at work and this last incident has tipped me over the edge and I am off with depression and stress. I do have other issues going on at the moment and simply cannot cope with this man any longer. My manager is of the opinion that this man is annoying (he gets annoyed too) but that the man in question cannot help it because of his condition and I need to sick it up and ignore him.....I can no longer do this. What can I do? I love my job and get on with everybody else.