falling in love with married man

Hi, I am in very difficult situation. Please help me,
It started 2 years ago,
Ok, first I moved to a place and I met one guy there who is 8 years older than me. He is not married but he is engaged. We were just friends and we used go out together sometimes, like friends, and I know his wife a little bit. They were my neighbours.
As time goes by we really begin to like and atrract each other. I knew that he has a fiance and it was wrong to love him, but i couldn't keep my feeling.
So like before i move from that place he suddenly kissed me and told me that he likes me a lot, so we told each other what we feel. I had a sex with him the other day, I knew i did bad thing sleeping with him, so i thought i will not see him again, but we met several times after i move. But he was telling me that i am young i need a boyfriend, think of your future, but i can't forget him, he is MY FIRST LOVE, but i am not gonna drive crazy and be his mistress, what I am asking is that I just want to love him some how? I just cant let him go, he thinks everythin is over, but for me its not, what should i do?

help me

He used you, but he is going to spend his life with his fiancée. It was wrong of him, but many men behave like that. Try to find an honest and faithful man next time.