How do you say it is over with your boyfriend?

Because you once had a serious relationship with this person and also loved them once they deserve respect and left with some dignity so you are going to have to choose a time when you are alone (TV off) and express your honest feelings with him. Let him know it's nothing he's done, but sometimes people just fall out of love. If you just want to be on your own to be free, then tell him that. You are the only one that knows the true reason why you want to leave him.