Most Helpful Girl
Mentally unstable people often attract other mentally unstable people.
Attractive looking people often attract other attractive looking people
Racist people often attract other racist people.
A Non racist would most likely avoid dating a racist person.
A mentally healthy person would most likely avoid dating a mentally unstable person.
Then you have all the variables in between. Dating has to be beneficial to SOME degree for anyone to engage with another person. It can be a solely sexual benefit, or it can be purely emotional, and any other combination of benefits.
Physical attractiveness can keep someone around for SOME amount of time. But looks get boring, and looks fade. IF a guy only uses his looks to get women, he's not going to have anything to fall back on once his beauty fades.