I have suffered with erectile problems as you have described about your husband for all of my life, so I hope my experience can help you.
First of all you and he need to know that you are not alone. This can and does happen to men of all ages and couples. It *****. There are many, many men who suffer from this. But it is very likely that it can be easily treated and get you two back on track...
1. I'm sure that the problem is hard on you. It is hard to believe that it is not you when you are going thru this. But since the problem has been with your husband and your relationship since the beginning it would be more likely that it is something he has always carried around with him and not you. Were there problems in that area before the marraige?
2. Your idea that he could be depressed or anxious is most likely correct. Depression and Anxiety are very commonly found together. My erectile problems caused me depression most of my life. Even if it hasnt been a problem all his life, it could quickly become a big problem in his head. Being anxious is very unhelpful for maintaining an erection. But surprisingly once you do have an erection it sometimes can cause one to "arrive" too quickly as well.
He needs to speak with someone for sure, if you get him to do it. Perhaps "he needs an annual physical?" That would get him to the Dr. Starting with a General Practitioner would be a good thing, to give him a full physical and get his testosterone levels checked. You never know if that could be the problem. They can also give him some sample Cialis, Viagra, Levitra so he doesnt have to go to the pharmacy. Or I bet you could get it if you went to your Dr. or gyno. I know that Cialis works. Trust me!
But he needs to be interested in sex and stimulated in order for it to work, so depression could be the problem.
I'd be happy to speak with you more about it if it helps you and him avoid what I went thru. I figure that there must be some reason I had to put up with it all my life.
I'm sorry to hear that you do not have anyone to confide in about your marital problems. You've certainly been doing the right thing by trying to talk to your husband about the issues you two are having and how it is affecting your relationship. I wish your husband were more receptive to talking. However, for many men erectile problems are very embarrassing, but I agree with you that he should see a doctor - especially now that he knows this is putting a strain on your marriage. Does your husband have any signs of depression? Is he on any medications that might cause decreased libido / erectile problems? Does he get erections while he sleeps / upon waking up?