Moira welcome to our Forum. You have been unknowingly living a lie for many years and obviously have borne the burden of something you weren't allowed to understand. Plus having 2 neurodivergent children to bring up. It's all very unfair that you find this out at a time of life that should be a slowing down, not the Mindfuck it has become.
But you will get through this. Significant affection is actually the best basis to not totally destroy any chance of working this out amicably.
I hope you have a good friend or family member you can talk to about your options. As well as the Forum you need face to face conversations with people you trust. You have decisions to make and the fact you're both okay with each other could possibly mean you can have honest, meaningful dialogue with him.
I lived with my former partner for 3 yrs before we separated. No intimacy, we were comfortably living together until I finally felt it was time to leave
Please keep reading the Forum and get advice from women who have been where you find yourself.
Elle