니가 you
그럴 comes from the word 그렇다, which means "like that"
(으)ㄹ 때마다 is a grammar pattern that means" every time (someone/something) [verb]"
(으) ㄹ 것 같다 is future sense of a grammar pattern that means "I think" or "it seems that"
So, "You do like that every time seems will go crazy"