Travellers - The Elusive Mary Matilda

My 2x Great-Grandmother is currently my biggest brick wall in the research of my family history.

Before starting my research I had a few limited bits of information about her, gained from family members:

• Her name, Mary Matilda. This was mostly known to me as my grandmother (her grand-daughter) was named after her.
• She died sometime in the 1930s. My Gran could remember visiting her as a small child so I could work out from her year of birth an approximate year of death for Mary Matilda.
• My Gran also remembered Mary Matilda to be "bed-bound" when she visited and had a vague recollection that she may have lived in a caravan. Supposedly, Mary Matilda had "broken her back when falling from a horse" and was a "bare-back horse rider in the circus".

So far I have found her in the 1911 and 1901 census as Mary Matilda HUDONS (married to Thomas HUDSON). Her death certificate confirms her death in 1933.

I have also found her marriage certificate and have the birth certificates of two of her children. These all give her maiden name as LEWIS and the marriage certificate names her father as Matthew WARD (deceased). 

Prior to the marriage in 1897 I have so far been unable to trace Mary Matilda. Both the 1911 and 1901 census gives her place of birth as Ashton-under-Lyne, Lancashire but I haven't been able to find a birth for a Mary Matilda LEWIS or Mary Matilda WARD (also having tried using each of the names Mary and Matilda separately) in the area. I have also tried searching for her in Staffordshire and Derbyshire where she later lived. Neither can I find her on the census for 1891 or 1881 in any of these areas. I have also I looked for her on the 1871 census although I believe her to have been born after this (her age on the later censuses and marriage certificate give her birth as either 1873 or 1877).