Problems with my girlfriend

Lately I have been having a lot of problems with my girlfriend because of different things. I feel so sad because I love her so much. I think that the problems are temporary because we always resolve our problems. But right now we are arguing because I confused her with other girl. But I didn't say that the other girl was beautiful, I just said that my girlfriend's glasses were similar with her glasses. I don't understand (why she is mad) jajaja