my advice is to say as little as possible. it seems to me that you are still attached to this girl, and, if you start talking, you'll either start wishing you were together again or you'll get angry about the breakup again. seeing an ex again is enough to bring up all kinds of upsetting feelings; talking about the past only brings up worse. and if she never got back to you about getting back together and she's the one who ended it in a cowardly way (i know what you mean; i had to practically tell someone to dump me, once, too, 'cause he was too much of a coward to do it himself), then you shouldn't bring up getting back together.