the most appropriate reason

I really don't think that there is no appropriate word to not hurt your partner. I really think that when breakups happen one is hurt unless otherwise the decision was mutual and you both have agreed on it. But if only you are proposing to end definitely the other party would be hurt no matter how courteous you are with him when breaking the news.

There is no way that you will not hurt others when you are breaking up. I have not experience being in a relationship but I still want to response. Approriate reason would be because its time to move on. Its time to face life of both of you separately, because its the only way to end it. Just be honest. It will never be easy, but you have to tell all you are feeling and explain your decision if you already have, explain that it will benefit not only but her/his as well.

in any case, if you want to end a relationship because you don't love your partner anymore,then there's no appropriate or valid reason that will not hurt your partner.you'll absolutely hurt him/her as well as you can't ease the pain..so just break it up with your partner and bear the thoughts that he or she's hurting but atleast its for the best.. happy mylotting!

I agree with most of the responder above,there's never a appropriate reason to break up,you basically giving the massage "i don't want to see you anymore",no matter what reason you gives can be hurt,but if i have to come up with one i guess,I'm going aboard or I'm gay\lesbian,can be more acceptable,be sure to let your unlucky love know this is your own issue and not their