I want the happy ending pls.. It will make sense on it's own if meanie end ups together happily

Hmmm how about both? I mean, you can choose one type of ending and write it first. After you've completed the story, you can give the readers an "alternate ending" sort of chapter. If so, then my advice would be do the logical ending first and then the happy one can be the alt. ending^^ its all up to you tho, hehe