Should i get together with a friend, will it work?

me and this guy have known each other for 3-4years, we worked really closely in work together for a year and we used told each other everything of our lives, after we both left that work place we had both continued talkin to each other about 3-4 times a week, we know everythin thats happens in each other lives and dont keep nothin secret from each other, i tell him more things then i tell my best friend, we kno wat each others bin thru in the past includin with our ex's, however recently he put it in a conversation about how im his ideal girlfriend and said maybe we should try it, i love this guy to pieces hes such a great mate and such a fab person to know, but i make such a mess out of relationships that i dont want to mess our friendship up cos we are really close , please help