Hi Lee - I've also had my thyroid quit working and am on Synthroid. It has a huge effect on your moods, energy, libido, etc., just like the other ladies have said. Also, I think if you're unfamiliar with what the symptoms can be (b/c they can be vague and subtle and may be attributed to other things) it can be hard to realize that there's something wrong. I had been having symptoms for months (and I'm an MD too), but never thought I might have thyroid problems until I noticed my neck looked different!
I agree with Jackie that standing by your W in a loving way during this time would show her so strongly how much you lover her ("In sickness and health, for better or worse..."). Continue to be patient with her, and give the meds time to get her hormone levels up to what they need to be, and I think you'll see some positive changes.
Maybe knowing your wife has this medical problem which is playing at least some part in her behavior makes it easier not to take it so personally??
Good to hear from you! Hang in there!
Mockers2
"Somehow we survive, and tenderness frustrated does not wither." Dennis Brutus, South African poet
"That which does not kill us makes us stronger."
Friedrich Nietzsche