Forget that first kiss, the first sex, the first tears of misunderstanding, the first fight. Forget the first amazing gift from them that says they thought long and hard about what you love. This gift is physical proof they tried their best to get you something concrete, in-the-hand wonderful to show the intensity of their feeling for you.
Forget it. Forget it all.
The first great real intimacy between two people begins when secrets are told. The time you stole money from the candy drive when you were a Girl Scout. The time you slept with your ex-sister in law after their marriage dissolved. That one shitty self-serving lie you told your boss which changed everything and ended up burning every bridge you had at the time. To this day you cringe whenever you think about having told that lie. And finally that secret about your parents you thought you would never, ever tell anyone.
But one day you do—you tell your new partner. No matter what happens to the two of you after that, they know the truth now and you can never take it back. They have the goods on you and you on them; your life together shifts permanently on its axis. It is impossible to predict whether that is good or bad.