@mummymaybe I understand how you are feeling.
When we first found out I has endometriosis I felt like I was going through it all alone. I would drag DH to appointments with my FS and we'd leave and I'd be upset about it all and he'd kind of make fun of me and say there's nothing to worry about whereas I was scared we'd never be able to have kids. He used to refer to it all as "my problems".
That changed when we finally got his SA done and it was a big shock for him to find out he had an issue to and sure enough we were off to IVF.
He came along to appointments with me in that first cycle but it still felt a lot like this thing that 'I was doing' rather than 'we were doing'... I did get quite upset and angry with him a couple of times and managed to explain to him how the anxiety of IVF infected every second with worry and that seemed to get through once he understood how much pressure I was feeling.
But when we lost the first pregnancy is when I think he really truly got on board.
The second cycle he simply couldn't take the time off work so he actually wasn't there for transfer (that I'm now pregnant from) but to make up for it he sent me a beautiful bunch of flowers from work. I also explained to him that it was important I felt like I could contact him with updates and he was really good at keeping his phone on and the volume up.
Little jobs like that gave him a way to be part of it that helped me feel less alone.
Anyway my point is sometimes it takes going through it for men to get it so your DH may figure it out a bit more as you press on.
It's important to try and explain to him how it makes you feel and how often it's on your mind as well as give him some clear instructions about how he can interact with you - simple things like him remembering to call you after appointments and check in on how they went.
Good luck, sometimes men can be slow learners but hopefully he will get it in the end.