"Unfortunately", self-esteem is very important.“If you don’t love yourself, no one can love you!”, “You need to be confident!”
It makes being rejected, relatively speaking, water off a duck's back.
If you treat the other person with respect, even when they reject you, you maintain your personal integrity, and that is critical when you are going through a bad period.
Trust me.
A wise man once said:
"If I disrespect you, I disrespect myself."
I would suggest ppl put the development/strengthening of their self-esteem/integrity on their priority list.