I've checked my Ottery St Mary Marriages from 1798 to 1837 and there is only one William Wilson marriage recorded - William Wilson married to Caroline Bastin on Sept 15, 1833.
On the IGI there is a Sarah Bovett married to James Wilson in Ottery St Mary in 1840
IGI
Sarah Bovett
Female Family
Birth: About 1821 Talford, , Devon, England
Parents:
Father: James Bovett Family
Mother: Sally Radford
Marriages:
Spouse: James Wilson Family
Marriage: 01 MAR 1840 Ottery Saint Mary, Devon, England
And James Bovett's parents are listed on IGI as John Bovett & Martha Selway. James and Sally had 10 children as listed on IGI
IGI
Husband
James Bovett
Birth: 04 MAR 1802 Ottery Saint Mary, Devon, England
Marriage: 27 JAN 1819 Ottery Saint Mary, Devon, England
Death: 1872
Father: John Bovett
Mother: Martha Selway
Wife: Sally Radford
The 1851 census shows Sarah & James Wilson in OSM
Name Relationship Mar Age Sex Occupation Birthplace
James WILSON Head M 34 M Ag Labourer Gittisham-DEV
Sarah WILSON Wife M 30 F
Elizabeth WILSON Daur - 10 F Scholar
Maryann WILSON Daur - 8 F Scholar
Harriett WILSON Daur - 6 F Scholar
Caroline WILSON Daur - 6 F Scholar
Wm. WILSON Son - 4 M Scholar
Tanny WILSON Daur - 1 F
Address: Alphington, Ottery St Mary Honiton, Devonshire
PRO Reference: HO/107/1864
Folio: 94 Page: 12
Sarah and the children all born in OSM
Hope this helps