It's a secret!

The other day I was told something in confidence.  It wasn't an earth-shattering revelation.  It wasn't a confession or information that would shed light on illegal activity or of a scandalous nature.  It was merely a conversation between me and another person.  Then at the end of the chat, the other person says to me "Keep it on the down low". 

That night while getting ready to go to sleep, I started filling Jeff in on my day and recalled my conversation for him.  When he realized I was telling him something that wasn't public knowledge, he stopped me in mid-sentence and said "Stop".   Jeff had no desire to hear any more and wished that I hadn't even told him what I already had.

Here's my thinking -- being married means that you can share this stuff with your spouse.  They supersede any pact or agreement given that you won't tell anyone else.  Right?  Not to my husband.  He has a very high moral code and wishes to not be brought into any third party conversations that aren't public knowledge. 

I argue that everyone would agree with me that you can tell your spouse.  Sometimes you want to bounce off what you heard and what a better person than the one who is closest to you? 

For example, what if my BFF told me she was cheating on her husband, but that I absolutely can't tell another person?  Fine.  I get that.  But, my gawd - how can I not tell Jeff?   How am I supposed to keep this secret to myself and not get it off my chest to anyone else? 

So I pose this question to you.  Do you agree with me that there is an unwritten rule that spouses can be told secrets or confidences told to you?  Now, of course, you need to determine in advance that this spouse being brought into the inner circle will not then go tell anyone else and can be trusted to keep a secret.   

I guess from now on, when I am told to "keep it on the down low", I'll need to clarify and see if that includes Jeff.  And I'd like to request that no one tells me anything that I can't share with my husband.  :)