who in many respects unwittingly seems hell bent on belittling and patronising you in order to feed their own ego and sediment their dominant social position?

I do. The thing that makes it more complicated is that this person quite frequently makes an effort to help me out when I've got a problem. It's just that some people seem to prefer you when you're in this kind of submissive position but can't deal with it when you're ready to assert yourself a bit.

What the hell do you do in this situation?

a.) Keep quiet
b.) Avoid them, bearing in mind they are in many ways the 'gatekeeper' to some of your other good friends
c.) Shout at them when they do it
d.) Take them aside and explain the problem