Err problem with my book idea..?

My main character which is a girl had a very close childhood friend but one day he had to leave, and move somewhere else. I have flashbacks of their friendship which makes me very happy to think about it. I guess people can relate to that case where you had this friend you liked. Since my story is very dark, I wanted to add a bit of "light" to it, and then I thought of keeping this idea! BUT...

My problem is when she gets older, she meets another guy, an they become friends, and the story goes around that. In other words, its the same thing with different details.

I really like both stories. I think the 2nd one is more important is because the whole story is around their friendship. I like the first one because i want to add some happyness to the story. I dont know if i should keep both or only of them because its kinda of same.

I hope it wasnt confusing