I agree with the letting him know that you will be treated with respect.
I know one thing that worked for me is when H was saying mean things I would say something like... Did you just call to say Hi or was there something else I could help you with? That took the air out of his sails and forced him to either say, yes, water I just called to be a jerk. Or to say hi. Then I would tell him I appreciated his call and would end the call.
