I'm not sure the word 'couple' means what you think it means

lol anyway...
yeah, I like what zappo said. just say something like "yeah, you guys are waaaaayyyy outta control, it's kinda like nerds gone wild" or something similar.
Or, if it's been too long just don't address it. Because you don't wanna come across like you've been thinking about the perfect comeback for like 2 days or something. So if she's aware that you've read it already and it's been a couple of days or longer, then just casually brush it off and plow past it. Something like, "haha, ya u guys are straight up crazy. So anyway..."