So over the years I've been both the dumper and the dumpee a few times and there are a few things that made me realize that trying to stop someone from leaving is just a plain bad idea...so here are my thoughts -- all please add.
1) It won't work -- by the time someone has mustered up the guts to say "I want to break up" they have given it tons and tons of thought and have committed to it in their minds. You can't negotiate feelings, actually doing so is just plain disrespectful. Like if I said to you I feel that chocolate ice-cream with sprinkles is terrible -- its a personal feeling (maybe its a bad example) but you can't logically sway my feelings.
2) You will actually push them further away -- lets just say you get through to that ONE soft spot in their heart that still holds feelings for you -- the other 90% of their heart is just going to feel guilt and people tend to run from things that make them feel guilty.
3) Whining, crying, acting all pitiful etc.. is REALLY unattractive and makes people uncomfortable -- to the point where they don't want to be around it. Have you ever seen your face when you are crying -- its ugly ... haha.
4) You will be always living on edge as to whether or not you are doing the right things vs. getting them close to breaking up with you again.
I say: work on a relationship while you are in it -- but once they say the words "break-up" you are basically doomed as a couple...for the time being -- MAYBE sometime in the future but don't cling to that hope.
Hope everyone is feeling good today -- for the first time in a long time I am.