Told my girlfriend she has to act a little more mature.?

So, my girlfriend will usually run and hide whenever we have an argument. After a day or two, she'll be ok and refuses to talk about the problem. So recently we got into another argument and I told her that she has to grow up and be more mature. I told her that after she cools down, she has to sit down and talk about the problem like grown ups. I'm 26 shes 24. Telling her to grow up, was a big mistake, she got so offended and won't talk to me now. It's been one week since we last talked. What should I do?