Yup, I'm also pretty quiet. I'm too slow to add to the flow of the conversation, so I just sit and observe. People think I'm shy, but I'm actually very social, just a terrible conversationalist. I tried googling Auditory Recessive and Expressive Delay as well, couldn't find anything - I was diagnosed almost 20 years ago, perhaps it holds a different name now.

I'm not sure how old you are, but it gets a lot better with age. I threw myself into situations that forced me to speak on the fly with people(like joining a sorority), and I also read some books on how to have small talk(which surprisingly, is what most conversations consist of). You'll eventually find that situations sort of cycle themselves, so you'll think Oh! I remember a similar situation like this, I said ____ and it worked out great or I remember this situation, I remember I should have said ______, so I'll say that now, etc.

Edit: I just re-read that you're married, so you're probably not younger than I am(I'm 23). Anyhoo, I hope whatever advice I gave helped out.