Is my DH being unreasonable or am I? Both of you are, in different ways, but that is quite ok and normal given the circumstances.
I have explained my feelings to him and asked him not to share my medical info etc But he has. So he is being unreasonable for doing that. Does he actually think he was reasonable to do that? Or is he sorry he went against your wishes?
I think though, expecting him not to show the scan pic of what is also his baby to his friends and colleagues is unreasonable, because the reason he wants to do that is that he's proud and excited about it, which is actually a good thing. So you are being unreasonable in asking that, because it's not only your feelings which need to be taken into account. He shouldn't share the other info though if you've asked him not to.
Although you are being unreasonable in not wanting him to show the scan pic, unreasonable-ness is one of the symptoms of anxiety, unreasonable and unhelpful thoughts are very much part of your illness. So yes, in some of this you are being unreasonable, but you can't actually help it because it's in the nature of your illness.
It would be great if he could understand that and therefore make allowances because of your MH, rather than just doing what he wants, even if what he wants is quite reasonable! But he is flawed and human, and perhaps doesn't have a deep enough understanding of how you feel dealing with your MH, unfortunate maybe but not unreasonable, it is probably quite hard to understand those depths if you haven't been there.