Most Helpful Guy
cuz people are shit (both genders) but you are not smart enough to know that and intimidate them or in another words through some barrels oil on fire.
Most Helpful Girl
Because it's someone you opened up with, gave a lot of yourself to and maybe even loved and they have betrayed you in some way which had led to them being an ex.
And people deal with the pain by talking shit/ venting their pain, anger, resentment... Emotions in general.