You can't think of it that way. Not at all.
I have been with my addict for 2 years also. And not once in those 2 years has he used ANY opportunity he was given to stay consistently, religiously clean, honest, dry, employed, none of it. Every time I have ever thought there was a light at the end of the tunnel of his addict brain & behavior, we have turned a corner & there has been another little white lie covering up more lies, stealing, manipulation, etc.
I miss my husband too. I miss the good times, because we did have those. I miss the person I know he SHOULD be and CAN be when he chooses to. But that is not the person he IS. And he is not willing to stick with treatment/counseling/etc in order to be the person he can be.
I have come to realise the hard way that the only time things were truly, really good between us is when I did not ask any questions. When I ignored my gut & accepted his lame & bizarre excuses or reasons for his behavior. When I deliberately chose to believe that things were "better" when under the surface they were anything but.
Please take care of yourself. The reality of these situations sucks ass. But you deserve so much better than this endless cycle of ups, downs & the blame game.
Hugs, I know exactly how you are feeling today.