Film from the early 90’s, I believe, where a priest at a monastery in (Mexico?) is bitten by a vampire but then refuses to feed on others. There is a bad vampire who feeds on the nuns. The good vampire priest guy finds a woman and falls in love with her but keeps the fact that he is a vampire from her. The bad vampire grows jealous of his friend falling away from him and eventually bites the woman so that he can have them all come together as a group of the same. This causes the good vampire to track down and kill the bad vampire. There is also a scene where they show a woman being burned at the stake on a hillside I believe. That’s about all I remember except that it looks like it took place before the 1900’s and it was definitely hot and took place in the desert.