Sleeping in Delta One

I have never been able to sleep on a plane. I’ve done more than 200 flights including to Europe and Asia, but never got any sleep. I also can’t sleep in a car or on a sleeper train or bus. I sleep well in a bed, but not on anything moving. I finally decided to splurge on D1 tickets to Europe (8 hour flight). I have resisted because it’s out of my budget and I have been afraid I still won’t be able to sleep. What is your experience of sleeping on lie flat seats? And please no comments from people who can sleep on anything.