The Teleologist: We aren't meant for each other.
The Deontologist: We aren't right for each other.
The Consequentialist: We aren't optimal for each other.
The Solipsist: It's not you, it's me. (My personal favorite, laikam...)
The Empiricist: I think we should see other people.
The Rationalist: I'm not a priority to you any more.
The Rationalist, v 2.0: I've been doing some thinking...
The Rationalist, v. 3.0: If you can't see your faults, there's nothing more I can say.
The Content Externalist: Ever since we moved, you've changed.