Why do you suppose he gets upset when you pull away? If he cared nothing about you, why would he care? He may not even realize why it upsets him, but he's responding to his own fear of losing you. People don't get angry about stuff that doesn't matter to them.
You are coming from a position of weakness. You can't go because of financial things...you rely on him. You don't want to push him further away (more weakness). You're scared.
Yes, it's scary. And yes, I know this isn't what you want, to end up divorced. Perhaps, since you aren't ready, the best thing for you is to start the motions of separating in your own home. Either move him out of your bedroom or you move to your own. Is it possible? Do you have the space? Start to withdraw emotionally from him.
Say to yourself, "We are done!" and mean it. It's okay...that doesn't mean it's over forever...but if nothing changes from how it is now, is it inconceivable that you're done? Is a life without him that much worse that a life with him when he doesn't love you and is with someone else?
He needs to see that you aren't his for the asking. Try it. Give it a week. Let him get upset that you are pulling away without telling him that you aren't. Let him wonder why you are fine. Take some "me time" and enjoy yourself...even if it's going for a walk as soon as he gets home and making it take an hour while you sort out your feelings.
Look at it this way...even if you end up together, you aren't tied to his emotions. You are your own person...you aren't just Mr. and Mrs aliveandkicking. You CAN be happy regardless. Life will go on. Don't look so far ahead...just focus on the making each day as good as possible and working to improve YOUR life.
You cannot be lonely if you like the person you're alone with. Dr. Wayne Dyer