I am planning a cruise for myself and finance' (as well as our wedding) I would like to wear a tux but my DF is allegic to wool. Is there such a thing as a non wool tux and where would I find it.
Yes, there's no requirement for a tuxedo to be made of wool, though I'm not sure where you can find one that's made of another material.
JTOL, another "black tie" option for cruising would be a white or pastel dinner jacket ensemble. Since white and pastel dinner jackets are properly worn only in warm weather (in the "summer," which becomes longer as you go closer to the tropics, and in tropical and subtropical climates), they are seldom made of heavy fabrics like wool. Since most cruises operate in warm weather, a white or pastel dinner jacket is quite proper.
As to your wedding, the proper formal attire would be a grey morning suit, with ascot, if your ceremony and reception are in the daytime. So-called "Black Tie" (tuxedos and dinner jacket ensembles) is strictly eveningwear, and thus properly worn only in the evening (that is, for events that begin no earlier than 6:00 PM).