Sorry for the delayed response - busy weekend.
I'm not a counsellor I'm afraid. However, I've been to relationship counselling a few times and a long involvement in voluntary youth work has given me some knowledge. But I'm far more geeky than that!
I'm really pleased you went for a walk with him, especially given how it worked out. That's good. And it shows what can happen.
Thinking more about your husband first, you say he is terrified of strong emotion. That seems a bit extreme. Men are often uncomfortable with emotions, especially strong ones. They certainly don't talk to other men about their feelings and may feel that men are expected to keep quiet about such things, even in this day and age. But being terrified of strong emotions goes way beyond that. I wonder why he reacts so strongly. What has happened to make him like this? I'm not saying you should try and find out. This is just something you might want to think about. I don't know if it helps to understand him.
You ask "was he nice cos he wanted sex". I'd like to take a look at that for a minute. Let me tell you a story...
I had a girlfriend who was a real pessimist. She believed that anyone who really knew her would hate her. She found it very difficult to accept that anyone might love her unconditionally. That meant that, whenever I did anything for her, she was always looking for a way of explaining it which didn't involve me loving her. When I bought her flowers, for example, her reaction was always, "You must have needed to buy some petrol", not, "You must love me." From my point of view both explanations could be said to be true - I bought her flowers because I loved her but it was also true that I often bought flowers at the same time as buying petrol.
Was he nice cos he wanted sex? Was he nice cos he loves you? Was he nice cos he loves you and wanted sex with you? Often the same event can be viewed in many different ways, some more positive than others. You can make yourself feel better simply by choosing the positive interpretation. Easier said than done, I know, but worth thinking about.
Yes, I'm avoiding the question of how you can help him see you are in trouble. If he did see it I think it is very likely that he would go into problem solving mode and come up with solutions like taking you out more often. That isn't really what you need but it is a typical male approach. But that doesn't mean you have to accept things as they are. You want him to empathise with you, to understand how you feel. That may not be easy but it is achievable.
Look at what happened when you went for a walk with him. You felt better and so you behaved differently. He responded and you ended up feeling even better. That is way more positive than anything you would have achieved by convincing him that there is a problem. You took control of the situation and good things happened as a result. Can you build on that?
Have you tried making a list of the things he does that show he loves you? If you think about it positively, you may find that list is longer than you expect.
I feel increasingly certain that you can sort this out. Good luck.
P.S. Have you ever read "Men are from Mars, Women are from Venus"? I don't agree with everything the author says but it gives a pretty good insight into how men and women think differently. It might help you to understand him. And, if you can get him to read it, it might help him to understand you!