Only just caught up on this as I don't use this email a/c regularly. Disgusted to read about your problems with Ryanair. Have you considered complaining to any Disabled Support group or making an official complaint to , I think it's CAA - yes, here it is
https://www.caa.co.uk/Passengers/Resolving-travel-problems/
Good luck & if you do pursue this, I'd be interested to hear the eventual outcome.