I think the best thing to do is to do some dives with another couple and swap buddies (I see some wise cracks coming on that one). My wife and I dive great together but what you mention is a common occurrence. Friendly advice may be taken as criticism. The fact is, we view advice/complaints/criticism our spouses say in a different (and usually defensive) manner. It may be best to have the same words and advice come from an independent source.