A different person
It would have been a great relationship if he had been more considerate, if he had made you more of a priority, if he'd been much more honest, and if he had been much more kind. But if he'd have been all those things, he'd have been a different person. So accept him as he is and let him go. That will make room in your life for the person who is all those things because he chooses to be, not because you wish he would become them.