Know why you like someone before you decide how much of yourself to hand them.

Liking someone is a feeling, and feelings do not arrive with their reasons attached. Sometimes you like a person because they have been kind to you. Sometimes it is because they are popular, or because they picked you. Those are different foundations and they hold different weight.

Before you tell someone the thing you have not told anyone, give yourself a minute with the question of why them. If the answer is that they were careful with smaller things, that is a good sign. If the answer is that you want them to like you back, keep the big thing a little longer.