Just don't open the door.. or answer the calls. If you have kids together (like I do) it's harder.. get a communication book going. No actual verbal communication or physically being in the same room.
...or...you could say,"I"m done, I don't feel like this is working between us....yea. Just did that this morning. :) fun fun
No way is going to be nice in the state he is in<br />
But im afraid thats not your problem.<br />
Anything you say nicely is going to sound mean to him if its cutting him out.<br />
Hopefully he will greive and then finally realise it was him and slowly learn to be a stronger person. If he doesnt thats unfortunate but nobody can get someone to that strong point but themselves