Contrary

Me and my girlfriend of a year and 7 monthes decided to call it off today, we've taken breaks and crap before but its serious this time. She's my best friend, but this sort of puts a damper on things. She asked me if we can still be friends afterwards, and i didn't quite know what to say, theres a whole question of jelousy if she finds someone else ( i didn't really want this to happen ) and the whole issue of getting over her isn't as easy if we still talk and hang out with eachother with other friends.
My question is if anyone has been in this situation before, how'd it work out? Like i said, i didn't really want this to happen, so i still have strong feelings for her, i just don't know if its a good idea to stay friends or to just block her out completely, or at least until i get over it.

thanks!