Mine are older teenagers now and I think I've just blanked out all the bedtime battles

I don't have advice per se - just a word of hope. "This too shall pass." I've always found it hard to believe that difficult things won't last forever (and ever and ever and ever...) but they never do. One day, sooner than you think, this bedtime battle will be over and you'll wonder "when exactly did this end and what did I do right?" Best wishes to you and remember, small children are just as confused by their strong feelings and new power to express them as we parents are.