There is ‘man time' and ‘woman time.' For men, time goes by faster than for women. Einstein tried to explain this with his theory of relativity and I think it was all about trying to get along with his wife. So, the next time a guy doesn't call or text a girl back right away or it's been two weeks since he last said ‘I love you,' just remember that it doesn't mean he doesn't care it, it just means that time passes differently for him.