If he really loves you he'll be with you no matter your decision on sex. Only have sex when your ready, and if he keeps pushing the issue make it clear that you wanna wait; end of conversation.
Honestly even though "I love you" should be a strong term, its lost its meaning with the low moral now-a-day; meaning, any guy can spew a bunch of garbage about you being "the one" so be careful and dont let all the sweet talk go to your head.