Maybe sometime when you and your roommate are talking in a good mood and it feels right, you could say something like, 'You know, I might be on the Spectrum, too' (if you're too roundabout, he might think that you're trying to push him to say that he may be on the spectrum)
I think I have a similar memory for the spoken word, and not just in movies. Although seeing a movie again gives me a chance to check it, and sometimes I'm slightly off in the exact words. But I've got the gist, the feeling, the plot point, the hinge point, so actually I think it might be a better ability than just a straight exact memory.