HELP!! I'm looking for a similar gay movie... somewhat.

OK, I can't remember the title of this other movie I saw before. I remember I saw it some years after I saw "La Mala Educacion."

DETAILS: The film is in Spanish. It could have been an Argentinian, Mexican or Spanish film. The story was about this brother and sister who has an almost incestuous relationship. Their mother was a former actress and was in her deathbed, or something. And the brother turns out to be gay and falls in love with a guy from his school... but the sister got jealous because she's the one who has an incestuous feeling for her brother. And I think the movie ends with the brother leaving with the boy from school. Or, not. I can't remember the ending.

I know this movie won some kind of award, maybe for cinematography. I remember I really liked the cinematography. Will someone pleeeease help?