The postcard says as you can see, that this church is located in Cabanas, however when doing a search on the net, its location is in Conceição de Tavira. In 2013, the parish merged into the new parish Conceição e Cabanas de Tavira, this might explain the confusion.
As for who sent this postcard, there's no confusion at all. It was sent by Leninha after winning her lottery on FB.
This church goes back to the first quarter of the 16th century. The façade's portico features a late-Gothic Manueline decoration.