I'm really, really sorry that you're in this situation. This process is difficult in so many different ways on its own - emotionally, physically, mentally. Dealing with something like this on top of that must be horrible.
One thing that stood out to me while reading your post is the fact that it seems that you're the only one genuinely trying in this situation. Trying to communicate, trying to suggest solutions that could be helpful, trying to work out the timeline working for both of you.
I'm sorry, but that's not how relationships should be like. Yes, of course - things aren't always perfect. But you should not be in position where you cannot communicate your own feelings and worries during such a difficult time without being afraid he's going to get defensive. You should have an opportunity to talk about your feelings and worries knowing that you're going to be listened to and actually heard.
I absolutely understand that we all go through different stages and emotions, we all react and behave differently, but being able to talk about things openly should be a given on both ends.
It's clear that there's an underlying issue that your partner isn't talking about - is he worried about something, is he realizing that he doesn't want to have any more children but feels guilty possibly taking it away from you? There are so many possibilities.
I'd honestly try to have an honest conversation with him one more time and try to tell him how you feel. If he gets defensive and doesn't seem interested in resolving anything - I'm sorry, but if I were in your position, I would really reconsider my relationship with him. I'd probably put the process on hold - maybe get my eggs retrieved and frozen for the time being, until I'd have some sort of idea of what's next.
You shouldn't feel lonely during this time, you shouldn't be left guessing and trying to come up with reasons. You deserve honesty and open communication.
And of course - you deserve to have a baby with someone who wants it just as much as you do, and who's going to be just as involved as you.
Just as a side note - my partner and I are currently going through our first round of IVF, so from the perspective of a partner who's not going through all the tests, shots, scans, etc. I can tell you that I simply can't imagine giving my partner a could shoulder or not supporting her in every way I can during this time.
I hope you two can talk about it and you can be heard. Take care x