I am in the same situation.

I have been in this relationship for a couple of years.  The first year had been OK, but since the beginning of the second year, I started to feel not being able to imagine sharing bed or even house with this man.  It has been a year already that I have been thinking about ending this close relationship and remain only distance friendship, so that I could find someone new.  I still don't know how to make a clear cut on this.  From time to time we are still together (but we don't live together).   I don't have enough guts to say thing straight on his face that I am not in love,  the worse thing is, actually, I have never been in love with him because of his attitude and, sometimes, bad personality, and above all, I don't trust him for some reason.

I want to move on without having him as the agenda in my life that blocks me from moving on, but I am too weak to say it directly.  I am thinking about just getting vanish,  no reply on either phone or email.  Is this considered bad manner?