This could be a wedding portrait. Gainsborough's couple are wearing costly clothes and perhaps the lady had a marriage contract in her hand. They do not seem to be in love. They are not looking at each other or communicating in any way and Gainsborough has separated them with a dying oak tree. 

Stik's couple are equally disinterested in each other, have no symbols of wealth or status, and are separated by a drainpipe.