Telling him you don't want to be with him anymore...

How do you tell your partner you don't want to be with them any more? I'm just no longer in love with him. We have been together 7 years, have 2 kids. I just feel awful for this but it's starting to become obvious I'm short tempered with him, no longer intimate with him and to be honest he just imfuriates the crap out of me some days. I don't want to drag the kids away from their dad nor have a broken family. I don't know how much longer I can do this for....

Before anyone states there is no other guy, I am not cheating nor will I.