He doesn't believe that people can change, well of course people can change. People can look at there life in a certain way, see things clearer like you have mentioned. If you can look at the things that have happened in the relationship and learn from them. That is you changing because you are able to see some things that have went wrong. I don't think the solution is staying away from him because you care about him and I think he needs some time to think about things. But this doesn't mean you have to walk out of his life. He said he loves you, you don't walk away from someone that still cares and loves you. You both need to keep in contact and see if things can be resolved. It's been six years for both of you and this is a matter of just working things out maybe even as friends to see if things can start over again and be different this time.