If you had written that there are specific times (during an episode) where he generally lacks a filter (different subjects, random people) and is just as suprized as you are by what pops out of his mouth... Then sure, I can say I relate to that because my filter malfunctions at times.

But you mention that its "constant" this issue where he shoots off his mouth with total disregard to your feelings and he has a favourite topic too.

I must agree, from what you've written, he sounds pretty racist to me.

Just because he's dating you, doesn't prove he isn't racist.
I've seen it over and over in my life, where the friend, gf/bf is the "exception to the rule"...