How to let my friends to be close to me again, when i actually quarrel with her before..?

This is how the story goes, she quarrelled with me and she didn't talk to me for about 4-5 months. Now she rarely talk to me, but is it difficult to live in the past again? I want to live in the past which got many fun, not like now, not even a single fun at all. what can i do to make she and I to go back where we supposed to be? How to let the fun and enjoyable to be return? Can anyone help me?