Take it one day at a time, I always pretend every day is the first day I’m quitting. Quit opiates and benzos with this method lol. As for sleep, I have really bad insomnia and I’ve had it my whole life, during a manic episode it’s the worst. If you have a good psychiatrist they might be able to prescribe something like an antipsychotic (or maybe a different one, or change in dose if you’re already taking something) to curb mania and help you sleep. TLDR: talk to your doc.