Can anyone tell me a possible meaning for a marriage between yourself and somebody else in a dream? Or is this just wish-fulfillment?

If you dreamed about marrying someone you are in love with in waking life, then it could definitely be wish fulfillment or it could be your unconscious acknowledging signs that you have felt that the other person wants to marry you as well. It could also just represent the "marriage" of two different parts of your personality. Here is some info on wedding dreams that might help you.

Thanks, yeah. I think that's what it was. Especially since I've just become engaged.

Congratulations!