I don't want to start a controversy but what make, model and year of your fridge and do you have a manual or have you looked for one?
My Dometic is older than most and the drain tube is also hard and brittle, mine terminates with the plug to keep bugs out and in a plastic cup. I was in an RV store someplace and saw the plugs and bought a package of two for about $5.00.
I can't find Dometic fridges in my catalogs so just for kicks I'm going to Google them or look them up on Chris Bryant's site to see if any have the tube with a "U" trap bend in the hose.