He said he's trying. It doesn't feel like he is
Read that again. And again. He can SAY anything, but it's his actions you need to listen to. He can say he's trying all he wants but if he's not then he's not. And that's your answer.
I keep thinking if I be the best I can be and make his life as good as possible and give him amazing sex. When/if he does leave he will eventually miss me
I'm so sorry for you. Honestly, a year ago I could have written this myself. I did everything for him. I cleaned up after him, cooked all his dinners, had lots of sex I didn't really feel like having, I was the perfect wife. I was actually really quite pathetic. And you know what? It doesn't help. Like @Zaphodsotherhead says, all it does is make you feel even more shit.
It took me far too long, but I eventually realised I was being a complete and utter mug and that actually I was worth more and deserved better. I finally said enough, and told him to leave. I was utterly heartbroken but honestly it needs to be done, these situations will never turn out well. You can't keep up the stepford wife act forever and be truly happy. It won't make him love you.
As I mentioned upthread - we are together now, he wanted to come back, said he'd truly realised what a twat he'd been, he's made changes to improve his mental health and puts more effort in. But had he not come back, then that would have been my answer. Or if he'd come back but not bothered making effort (basically what your H is doing now) - again, that would have been my answer.
You are worth so much more than you believe right now, I promise you. And no matter how this turns out in the end, you WILL be ok. But you can't allow yourself to be tortured like this. I wish I could give you a hug x