Love / What do you make out of our relationship (chinese girl with a Polish man? [8]

Well, I am 24 Chinese and I met a 58-yr-old Polish man (married with a daughter older than me). We started sending email to each other everyday. He's a sweet guy but... what does he intends to do (or rather, what is he trying to do?) He says he likes me and thinks of me until he sees me in his dreams and he likes talking on the phone with me... But I thought he is already married.. why does he still do these things? - Causing me to misunderstand as well...