First, I would stick to just taking 5mL of G, and doing everything you can to avoid taking more.
I don't know exactly how pregabalin would help as I don't have any experience with GHB dependency, but I imagine taking 300mg two to three times a day will help a lot with your symptoms. Keep the GBL on hand for the first couple days though, because I don't know if the pregabalin will be enough on its own, you may need to supplement the pregabalin for the first day or two with small doses of GHB (1-2mL) before you just take pregabalin.
A longer acting benzo like diazepam would be ideal for your situation, you could just replace the GHB with that for a week and you should be out of the woods, and then you can take pregabalin to mitigate any other symptoms. Ideally you would be able together a long acting or moderately long acting benzo like diazepam or clonazepam, as opposed to a shorter acting one like alprazolam.
Taking seroquel will be great to have to help you sleep at night and quell any bouts of anxiety you experience during the day, instead of just taking more G/pregabalin/benzodiazepines.