Her birth index:

First name(s) LUCY POWYS
Last name COBB
Birth year 1857
Birth quarter 3
District BRECKNOCK
County Breconshire
Country Wales
Volume 11B
Page 98
Record set England & Wales births 1837-2006
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Her baptism index:

First name(s) LUCY POWYS
Last name COBB
Birth year 1857
Baptism year 1857
Baptism day 02
Baptism month Aug
Place BRECON, ST JOHN THE EVANGELIST
Mother's first name(s) Emily Catharine Powys
Father's first name(s) Joseph Richard
County Breconshire
Country Wales
Record set Powys Baptisms
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Her marriage is on the indices for a husband surnamed one of Price, Maybery or Davies.  But in the 1891 and onwards censuses none of these surnames has a wife with the fornames of Lucy (Powys).  Currently, Oct 2016, the only answer is to get her marriage certificate.

But a footnote on FreeBMD says that the Davies marriage was to an Elizabeth Morgan so it looks like Maybary as the partner.  Price does not appear on the FreeBMD index.

Henry O A Maybery was in the 1881 census as a solicitor, town councillor and a Lieut in some Volunteers.  Sounds a likely husband.

Eventually found her in the 1901 census with a daughter and a son both born in Brecon:

First name(s) Last name Relationship Marital status  Gender  Age  Birth year  Occupation  Birth place

Henry O A Maybery Head Married Male 49 1852  Solicitor  Brecon, Breconshire, Wales
Lucy P Maybery Wife Married Female 41 1860  -  Brecon, Breconshire, Wales
Muriel P A Maybery Daughter Single Female 9 1892  -  Brecon, Breconshire, Wales
Richard A Maybery Son Single Male 6 1895  -  Brecon, Breconshire, Wales
Caroline E M Carden Visitor Single Female 48 1853  Living On Own Means  -
Alice Baskerville Servant Single Female 29 1872  Nurse Domestic  Herefordshire
Elizabeth James Servant Single Female 20 1881  Under Nurse Domestic  Herefordshire
Annie Davies Servant Single Female 39 1862 Cook Domestic  Llowes, Radnorshire, Wales
Emily M Hayward Servant Single Female 21 1880 Parlour Maid Domestic  Hereford, Herefordshire
Emily Evans Servant Single Female 22 1879 House Maid Domestic  Rhayader, Radnorshire, Wales

Address:
Town Brecon
Parish Brecknock St John the Evangelist
Country Wales
County Breconshire

Census ref:
Archive reference RG13
Piece number 5168
Folio 58
Page 5
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In 1918 she was listed in the London Gazette for some award:

Mrs Lucy Powys Maybery, Commandant, Voluntary Aid Detachment No 18, Brecknockshire.
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Her death index:

First name(s) LUCY P
Last name MAYBERY
Gender Female
Birth year 1858
Age 88
Death quarter 1
Death year 1946
District BRECKNOCK
County Breconshire
Volume 11B
Page 73
Country Wales
Record set England & Wales deaths 1837-2007
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Her probate index:

MAYBERY Lucy Powys of Nythfa Breconshire widow died 2 January 1946 Probate Llandaff 30 May to Muriel Powys Aveline Fowler (wife of lieutenant colonel Hugh Griffith Coke Fowler D.S.O.) Effects £18058 19s 3d.
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Their marriage index:

First name(s) LUCY POWYS
Last name COBB
Marriage quarter 4
Marriage year 1884
MarriageFinder™ LUCY POWYS COBB married one of these people
JOHN PRICE, HENRY OXENFORD MAYBERY, EDWARD GRATRON DAVIES
District BRECKNOCK
County Breconshire
Country Wales
Volume 11B
Page 149
Record set England & Wales marriages 1837-2008
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Their banns transcript:

First name(s) HENRY OXENFORD AVELIN
Last name MAYBERY
Banns year 1884
Banns day 19
Banns month Oct
Marriage year 1884
Place BRECON, ST JOHN THE EVANGELIST
Spouse's first name(s) LUCY POWY
Spouse's last name COBB
Bride's parish St John
Groom's parish St Marks, Nottinghill, Middlesex
County Breconshire
Country Wales
Record set Powys Banns

In fact the banns were read first on the 19th october and then on 26 oct and 2 Nov.

In the margin is written ‘Married’.
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