Katie1, that seems more than a little harsh. The OP is having a hard time, try to put yourself in her place, please.
Plenty of people have a long term relationship outside marriage, I certainly did. You don't need the ceremony to be committed to someone.
Dillsandwitch, take a liitle time to talk to your SO, he may be as shocked as you. Don't rush into actions you might regret later. Courage!