From someone who also has had trouble with anxiety in the past (not just flying) I hope I might be able to offer you some help. Everyone else has been quite thorough though so not sure how helpful I can be beyond all of their lovely words. OK so first of all, as I've said I have had problems with anxiety and panic attacks in the past and I assume half of the reason that I am scared of flying is not actually fear of the plane or the plane crashing etc but fear of the actually having a panic attack itself. I don't know if this might be the same for you but I have found a few things help. Usual coping techniques when I'm panicking wherever I am, which anyone who panics knows can be different and at a variable controllable level for different people. For me it means getting my breathing under control and funnily enough giving my mum a call. I also have a playlist that helps when I panic....a lot of it as you might know is just mind over matter. The playlist has calmed me down in the past so just listening to it now I associate it with being nice and calm.
Also you mentioned you were worrying about letting yourself and your husband down which can only make the panic worse. I know it might be hard but try and take some of the pressure off by thinking 'if I dont go I won't be letting anyone down but if I manage it then great' Just keep talking things through etc.
I don't know if any of that is relevant to what you are feeling but I do hope it helps I know how awful being scared of flying can be and how much the anxiety can feel its taking over so I hope you can overcome it and make it on your flight.
Also you mentioned you were worrying about letting yourself and your husband down which can only make the panic worse. I know it might be hard but try and take some of the pressure off by thinking 'if I dont go I won't be letting anyone down but if I manage it then great' Just keep talking things through etc.
I don't know if any of that is relevant to what you are feeling but I do hope it helps I know how awful being scared of flying can be and how much the anxiety can feel its taking over so I hope you can overcome it and make it on your flight.