Wat 2 say, ual curiousity?

a guy im seeing is freaked out because I told him I have had a same experience when I was a teenager.. and now hes freaked out calling me a . it was a one time thing... and also my ex of a long time turned out to be a real loser... into drugs, and a deadbeat dad.. and im trying to justify that its not a reflection of bad or poor judgement, and thats not my character... Im writting him a letter.. but I can't find the words to justify this. pls help