Infatuation

I have a question to all who will be willing to give me some advice. I am engaged to be married next year. I am 26 female, who is so in love with my fiancee. We are perfect for each other. We are so compatible.

A year ago I used to work at this big company. An old co-worker used to talk to me. He caused this big racket at work, telling me how he wasn't going to give me my b/f's messages at the time when he called. He bitched/yelled/did everything to make me feel uncomfortable. I wanted to quit so badly. After he was done maybe after two months of being an ass, we became friends. i thought of him like a good friend at work. he helped me with my computer so many times because it always had problems.

I got laid off before him. He is still there. To make a long story short, i still keep in touch through email and now Yahoo IM. I do tell my fiancee, i dont hide anything. I tell him the conversations too. he knew him when i used to complain about him at work. My question is i think its infatuation, but how can i tell? I am in love with my fiancee, but whenever i am bored when he is at work(im unemployed) i talk to this guy. I flirt, not a bad flirt, just a bunch of bull **** or insulting him. I sometimes talk all day long with him online-email. And when i dont hear from him, i get all weird.

I care about him. I know why I talk to him. He makes me laugh, more then when i am with my fiancee. He makes me feel good inside. There is not one email I don't laugh in. I want to be friends always, and i know i cant'. if my fiancee felt that way towards a woman i would feel so unloved. but he trusts me. i trust me too. its not physical or sexual attraction. i am intrigued by his personality. last year he had a heart attack and it affected me. when i got laid off i told him i missed him and he said the same. At work he did ask me out(another weird story) for a long time he had a crush, but i dont know. I dont know anything anymore about this thing. I am obsessed. He is an older man (late 40's)

i need advice.