Ellen:  As an Ob/Gyn NP, I can answer your questions.

It's not necessary to treat your husband for a yeast infection, unless he has
symptoms.  That's very unlikley in circumcised men.  If he does develop
symptoms, he can apply micatin 2 % cream, available OTC, twice daily.  Good
handwashing after you use the bathroom should prevent transmission of thrush
to your child.  Monistat is effective and safe for nursing mothers to use.
 (The safety of the newer, prescription antifungals in nursing is not yet
established.)  It's not necessary to treat yourself for an asymptomatic yeast
infection.  Improving your diet could help your body re-establish its normal
balance.  As far as yogurt tampons are concerned, you can insert them once
daily at bedtime for a week.  Good luck.