Most people say "I love you" all the time — to their parents, their siblings, their friends, their dogs — but when it comes to saying those three words to a partner for the first time, they freeze. And any fan of cheesy TV dramas can probably understand why saying "I love you" feels monumental. Remember when Dean told Rory that he loved her on Gilmore Girls? Her response that she needed to think for a minute resulted in the first of their many breakups.
The issue there is pretty simple: Don't date a Dean — and don't be one, either. When Rory said that she needed time to think about how she feels, Dean should have allowed her that time. The first rule of telling someone you love them is recognizing that they might not be on the same feelings train as you, but that doesn't mean they don't care about you or won't eventually be ready to say "I love you," back.
So, if you feel that you're in love with your partner and you want to say it, then say it. "If you feel strongly towards that person and feel in your heart that you love them, don’t let fear dissuade you," suggests eHarmony's advice blog. "Telling someone you care about how you feel is the first step towards building greater intimacy and trust." When and how you say those three words is totally up to you. As much as we might want guidelines, there are no solid rules on love. (Just, maybe avoiding sending an "Ily" text message).
But when you say your "I love yous," don't go into it with expectations. It's not fair to blame your partner if they're not there yet. And whether you say anything or not, disappointment on your face will probably feel like blame to them. It can help to hedge your language and say something like, "You don't have to say it back, but..." That way, you're giving your partner space to share their feelings with you. If they do say that they're not ready yet, accept that and move on. There's no reason it should ruin your relationship.