I was on Seroquel for about 15 days at one point to help my sleep too. It helped me, it seemed to reset my sleep.
I still have sleep problems now but I'm on latuda and remeron which make me very tired and result in at least 9 hours sleep. My pdoc tells me it's the depression that's causing the sleep issues for me.
I'm glad the gabapentin is helping you. I also got a lot of benefit from it when I was on it. The only downside is that I had to take 3 pills, 3 times a day.