I know it hurts.... I always thought that if Im trying really hard to save the relationship they should be trying really hard too.....
My expectations of other, I have spent years and years hurting myself because of that.... Unfortunally he is not ready to work on a relationship and if he has only been sober 3 weeks and has no support ... I would not expect much from him.
But for you there is lots and lots of hope, work on you for now, dont worry about the relationship .... just worry about you and what you can control.