Erupted Affection after 10 years of Dormancy

I woke up one day and found myself deeply, strongly and madly haunted by the nostalgia of a man i met 10 years ago whom i didnt have any feeling for all these 10 years, whom I only saw for twice. It’s very strange phenomena for me, as I am totally passivementally. I never thought I would desire him. this feeling emerge in the midst of my most quiet and private environment and emotion,so it may be something about me towards this man. I don’t know. Perhaps, I’m too lonely. I m thinking to write a message to him to express my feeling. am i insane, crazy, too extreme to do so? please no junky, rubbish, vulgar comments. sincere comments and experience sharing only. thank you.