boyfriend issues

Well, I have an important question: when is the right time to say 'I love you'/when is it too soon to say it? My last boyfriend was a long relationship and he was the first person I ever said 'I love you' to. However, he cheated on me for 3 or 4 months and it messed with my perception of love. Now, I have a new boyfriend and I'm hesitant to say 'I love you' because of my past, even though my new boyfriend is nothing like my last boyfriend. So, when is too soon?