Don't do it by phone. Hanging up without being able to hear the other person out fully is too much of a risk. It is most frustrating when you can't express properly. Instead write him a letter explaining how his accusations made you feel. Handwrite this, don't type, email or text, make it personal, it is a big deal you know? You can put that you are considering breaking up with him as a consequence of his actions. By the time you have finished writing the letter you will feel a lot clearer about the situation. You then have a chance to read it back and reconsider things before posting it. If he truly wants to save your relationship then you give him the option of coming to you to sort it out. He is the one that has been out of order here. If he can't be bothered to come to you to sort it out, then I would see the relationship as over and you don't need to spend the trainfare and pussy foot around finding the right moment to tell him.

It is really up to him whether he is "hurt" by your conduct. -Do you really have that much control over him that you can consciously "hurt" him? Have you considered the possibility that he may not be hurt, that he may only be upset, or may even be happy you took the initiative and broke off the relationship?

There are clear trust issues here. The only reason that he'd be making these allegations is because he is insecure about the relationship, you act like you have something to hide.... These are only a few suggestions to his behaviour (since I do not know much about your relationship with him) and I see no reason to break up if you two really love each other. I suggest meeting with him and reassuring that you are faithful and there are no reasons he should think other wise. Give him another chance, trust is hard to maintain when one is insecure and in a long distance relationship. From what I gather, he feels as though he is not 'worthy' to have you and assumes you are cheating because of it. Give him another chance; however, if you feel as though his lack of trust is dissettling and you NEED to end the relationship, do so in person. BUT, just because you have been accused it is not substantial to break up. Make sure you want to break up for these reasons and nothing else, don't be clouded by this and find an easy excuse to get out. You two need to build trust and communicate. My girlfriend and I have been dating for over 5 years and 4 of those years have been a long-distance relationship (because of university). We did have our issues, but we grew to trust and love each other. Hope this helps, Good Luck!

Bad. Very Bad. Try to see him for the last time. Then tell him.