You have to get out of this for several reasons, man.
First and foremost, you don't love him nor do you want to be in a relationship with him. Breaking up is going to hurt him, there is no way around it. But you are hurting yourself and setting both of you up for a much harder fall the longer you avoid it.
Second, he knows you want out. Combine this with that he manipulated you to get into the relationship, probably manipulated you to move in, and you have a relationship that is based prinicpally on will power and not on actual feelings, chemistry or a connection. He is continuing to manipulate you by forcing this dead/dying relationship to exist and it's now just a sham. He knows you have a conscience, and that he can use your desire to be a decent person and not hurt him to get what he wants from you. He is holding you accountable for his happiness, which is a common problem in relationships, but is a destructive behavior pattern. It's not your job to make him happy or to fix him or something in his life. To do so is to ask something of you you cannot deliver, and therefore sets you up for failure. This is a power game, and you're the victim. Tricks are for kids, get the fuck out.
Third, he's too old not to know better, and you shouldn't have to teach him how to have a relationship like a grown up. Try dating a grown up instead.
Fourth, breaking up is a decisive action, not a democratic one. This is a life lesson you both need to learn.
You are being used, and have been since day one of this "relationship." It's time to stop.