While waiting for the cert of Martin Winn marriage to Mary Storey, I did a search on Durham County Council registers online. I found two results for a marriage to Mary Storer in 1864.
#41 STOREY Mary 1864 and #42 STOREY Mary 1864
One is to Martin Winn = STOREY, Mary, Year1864 marriage: WINN, Martin
The other was STOREY, Mary, 1864, DAVISON, Robert A
But in 1861, STOREY, Mary married FORSTER, Robert F
In the 1861-70 period there were no Mary Forbes married in the register, not until 1883 and that was not to Martin. Out of curiosity looked at convicts, Storey and Forbes but none fitted the time or place. Also looked at Wills. There was a Robert Storey a farmer, from Ferry Hill died 3 April 1841.
There were Storeys and Forbes about but ATM no connection between them.