Chicory,
You KNOW what you have to do. There will never be a "good time" to make him leave. This is what he's been, and what he will continue to be. There may be a brief hiatus here and there when he senses you are about to lower the boom, but then he will be as he was during the last hiatus--martyred and hostile.
The ONLY way he has a chance at changing is by being forced to, by circumstances. They are circumstances of his own making, not yours. He has no RIGHT to live in your house, making you miserable. He is only there because you have allowed it.
You can stop it when you are ready. If you need help to get him out, you can get it. You can have a friend, a group of friends, the police stand by.
This is your LIFE. You have a right to a peaceful existence. But only you can make it happen.