This is the best, clearest vocations catechism I've seen (which I discovered on the SSPX vocations page (http://www.sspxasia.com/DocuŠ¼ents/Society_of_Saint_Pius_X/Vocations/index.htm)):
Vocations Explained: Matrimony, Virginity, Religious State, and Priesthood (http://www.gutenberg.org/ebooks/31311) (1897)
by a Vincentian Father (http://www.gutenberg.org/ebooks/31311)
It was approved by Cdl. Gibbons.
It is vehemently against mixed marriages, and it unequivocally states that it is de fide that the state of virginity or celibacy is better and more blessed than that of marriage (cf. 24th session of the Council of Trent on matrimony (http://www.ccel.org/ccel/schaff/creeds2.v.i.i.xi.html#v.i.i.xi-p5.6)).