Well I can definitely tell you that you are not nuts.........and this is not appropriate behavior. Though the reality is you know this already. With age comes wisdom.....at least for some of us Sounds like your husband needs some wisdom lessons!
Seriously, you know this is not ok. He knows this is not ok......but he also knows what you have just admitted to me. hat while it may be a breaking point you are not going anywhere because you feel it is just not worth the effort to leave. So in reality why should he change really.......he can get away with doing what he wants, and you let him do so. Sounds like the kid with the cookies.....even though he knows he can not have them why not take them if mom is not going to punish him.
That is not to say that you should punish him, but after this many years he needs to learn that respect is a two way street. You have given him the respect of being a honest wife and for that he is disrespecting you.
The fact of the matter is he is the one looking foolish.........everyone in the store including the women he is standing near knows he is with you, yet he acts like a teenager thus making him look like a fool. The sad fact is many men (Myself included) have been known to think our actions make us look cool, or attractive. And in reality we sometimes (Ok often) look like fools. The problem is he has not learned that he is looking foolish.
I would suggest sitting down with him and letting him know how foolish he looks. If this is a breaking point (Even if you will not leave) then it is a matter that needs to be addressed. Let him know that his behavior is not only making him look like the village idiot but is hurting your feelings. Let him know that just because you have spent the last 40 or more years with him is no excuse for him to begin treating you with disrespect and that as a women you demand that he treat you as the women he loves.
I never advise ultimatums, so do not do this. But do let him know that the time for foolish games are well past you both and he needs to concentrate on the women he loves instead of women that have no interest in him.
In reality he should be watching out, there are many men out there looking to start over with a mature loving women. And his actions could open the door for Mr. Right to try and swoop you off your feet.
I wish you the best in all this, and again you are not nuts!