I found that when ever I would tell myself that 'I lost desire to be sober' I was just giving myself an excuse to use. I wasn't using because I couldn't get sober, I was using because I just didn't have the desire to be sober.
Don't let your mind play tricks on you. You can get sober, you just need to put the effort into it. Even if you are feeling lazy, be lazy but sober. Sure hobbies are nice, but at this point you have one goal: get sober. Everything else should come second to that.
Look at it this way, most of us have woken up and not wanted to go to work. Every job at some point becomes boring and every day blends together but do we just quit and say screw it? No, we get up go to work and do it anyway. So instead of just losing the desire to be sober, don't look at it as an option.
I hope that you talk to a doctor, see a therapist, make a recovery plan, or do something to help you pursue getting sober. If you really didn't want it, you wouldn't come to SR.
You can do it, you just need to want it bad enough.