If you are not in a marriage and your mate says they want to marry, do you go ahead or seek a reason not to?

Disclaimer Even though you feel you have no need to marry or your mate would never ask, avoiding any answer one way or another will be a de facto negative, meaning you beg off or avoid marrying them.

You have lived for X amount of years with your mate and the notion of marriage never came up, or were quickly dismissed when it was, your mate, however, said they wanted to get married do you go ahead and get married or would you try to find reasons to not honor their wishes to marry?