Hi Lisa,
You have a very tricky one here. I have spent a lot of time trawling through but still haven't managed to find a marriage for Anna Marie and Henry Phillips.
I have found a little more info that may add to what you have already.
1871 census. Sarah Jane Huxtable a nurse, born Somerton living in East Retford district, Nottingham.
1871 census. Hannah Huxtable a domestic servant born Somerton living in Chorlton on Medlock, Manchester. Perhaps this is where she met Henry.
The 1911 census shows (*), so that would put her marriage during last 3 quarters of 1880 or the first quarter of 1881.
There are two possibilites, 1) they did not marry at this point, or at all, 2) she was married before and married Henry under a different surname.
Would it help to get another child's birth certificate as it might throw a new angle on the matter.
Best of luck with it anyway.
Elizabeth
1911 details removed - only details found in the free index may be posted.