I had a brief addiction to GHB (essentially the same thing). What I did was switched to phenibut. Phenibut is a GABA-B agonist and will totally substitute for GHB. However phenibut lasts a long time and is far, far easier to taper. You can take it once per day and it will hold you for 24 hours at least. You'll want to find the dose that's right for you, it takes a long time to come on fully. Get stable on that dose, only take it as little as you can to avoid withdrawal. Once you're stable, you can lower the dosage slowly, but what I actually have always done with coming off phenibut is just cut a day out. So instead of daily, do it every 2 days all of a sudden. The off day will be anxious and maybe hard to sleep, but it's doable. Then get stable on that, and cut out another day. Then another day. By the time you're doing every 4 days, stopping is not difficult, though you'll probably experience some rebound anxiety/insomnia still.
Also, alternating baclofen and phenibut will make it even easier, as phenibut is additionally a gabapentinoid (blocks voltage dependent calcium ion channels), which produces its own dependence, so really, phenibut is addictive via 2 separate systems, whereas baclofen is just a GABA-B agonist. The second time I came off phenibut, I found that taking baclofen every other time made the process easier.