I don't recall all the details, but a long while ago both Sherri and Elisabeth showed concern about the position pastors would be in if they refused to marry gay couples.
They cited a story about a priest who had been jailed for that reason, which I believe was proven not to be true.
I really can't remember much about the story unfortunately, but it just seemed like more fear-mongering.
Despite having gay friends, Sherri hasn't ever shown any support fit gay marriage that I recall.
I consider much if not all of her objection to be based on her religion.