As an Italian, I have to say that, with due respect, I disagree with what @Penelope and @Chantal say: I understand why you, Chantal, were using a spoon, not being used to eat Italian spaghetti, but your host family wasn’t going overboard when explaining our customs. As in Asia people use chopsticks, in Italy we roll spaghetti with the fork, it’s just how we do it. The only time you actually see people using a spoon is when dealing with little kids who have yet to learn how to roll with a fork.
Obviously it’s your personal choice if you want to learn or not a local custom, what I am trying to say is that your host family wasn’t lying about the way we eat spaghetti.
Concerning the sauce, I quote a statement above and then I’ll try to explain:
Consider that the Italian sauce is A LOT less “liquified” than the one you see in the US for example. It’s less likely to splatter yourself with it, as a consequence. When dealing with the sauce left on the plate once eaten all the spaghetti, Italians do not use a spoon, but do the so-called “scarpetta” (literally “small shoe”): you pick up the sauce with a little piece of bread.
So, that’s how we do it: just the fork for spaghetti plus “scarpetta” for the remaining sauce. Obviously, it’s a free world and everyone can do as one pleases, but I think it’s interesting to try local customs, when visiting a foreign country