i made a christmas cake and decorated it last week as i know that fruit cakes last for ever (well almost lol) . . . . . i used strawberry jam to stick the marzipan to the cake and now i cant get out of my head that it might go mouldy because it cant go in the fridge now its decorated. will it be ok?

I think you will be fine, I can't see that strawberry would be any more risky than apricot jam which is what one would normally use for fruitcake. Now the marzipan is on it the air can't get to the jam anyway.

How to make and use apricot or strawberry fruitcake glaze:

http://www.joyofbaking.com/ApricotGlaze.html

HTH

Any jam is fine. My Mum (and now me) have been using jam to stick the icing to our christmas cakes for years ... with no ill effects. xx