April fool’s day. He decided to play a prank by sending her an “I love you” text. She decided to use it as an opportunity to express her true feelings too, for in case he didn’t reciprocate, she could always tell him it was a prank and thus save face from rejection.
He sent the text. She ignorant of his devious prank, thought he had thought exactly what she had and fully reciprocated the feelings over text, including the part about her own plans.
As he sat staring at his screen, as the realization that he has just effectively ruined his friendship with her sunk in.