Here's her original thinking on the matter: http://www.portsmouth.co.uk/news/local/gosport-mp-against-move-for-same-sex-marriages-1-4752446
It doesn't sound like she was against same-sex marriage as a matter of dogmatic principle, rather she had concerns about the potential discrimination of people with religious beliefs. In other words, what she seems to be saying is that same-sex 'civil partnerships' and 'civil marriages' are already of equal status, in her opinion, and as such she didn't see a need to change anything to maintain that perceived level of equality.
Now, one can obviously disagree with her opinion on that, but I'm not sure that her position on same-sex marriages is necessarily incompatible with being an equalities minister.
On your marks, get set.....
#pull Trousers' post to pieces klaxon#