You're in a situation that doesn't seem hopeful even in spite of the fact that he seems to be 'trying' harder. Here's some stuff to think about.

It's totally understandable that you're tired now and worn out. You've worked hard to try to make things work, you've endured his behaviors a long time and frankly have been living with the hopes that he'd come around.

Thing is, I don't entirely agree with the idea that people can't and don't change but, rarely do they change because someone else tells them they have to. In cases where someone actually does change, it's internal. They come to a place in their own minds and hearts that they need a change, that they need to be different. When it's prompted by others, friends, lovers, family or otherwise, it typically will be short-lived. They do this to appease the other person, bring back the peace, or avoid the current conflict. But since it is not an internal need to change, the shift is only superficial and it reverts in time. There is nothing anyone can really do to change another person, in almost all cases.

Another thing to think about. I know this is not a domestic violence case but I think this point will apply. In domestic violence cases, abusers will be 'good' for a time, they call the "honeymoon" phase. They do this to get back on good ground and gain the trust of the victim again, but only for a time. I think this pattern of behavior, while exaggerated with abusive relationships, is true for almost all human relationships, but all without the violence itself. Instead, I believe you're in a honeymoon phase with your SO and he is doing this to appease you for fear of losing you. It is not likely a permanent change.

he sounds manipulative and likely is manipulating or attempting to manipulate the situation even now.