It's in the kiss. Kissing is the most intimate thing mates can do. I have the exact same problem with my wife. I've tried everything known to man. Nothing works. Deadend. Been with her 9 years now. Regret ever marrying her. There are some people that are just dead inside and it comes through in the kiss. No passion, Can't be emotionlly connected to anyone. It's in the kiss. I can guarantee he won't change. You don't do it for him. HE already knows that. Therefore being with you is commiting a crime against you. You can't love anyone you commit a crime against. So, it's a deadend. He's just using you and he knows it but will never admit it. No love in the kiss. Tragic for them really.
Do yourself a favor and move on. He'll drive you crazy with all the effort you have to put into it and still nothing works. I've already lost 9 years. Don't make the same mistake.