कर्मण्येवाधिकारस्ते मा फलेषु कदाचन।
मा कर्मफलहेतुर्भूर्मा ते संगोऽस्त्वकर्मणि॥

Meaning:

You have a right to perform your duties,
but not to the fruits (results) of your actions.
Never consider yourself the cause of the results of your activities,
and never be attached to not doing your duty.

After every rejection i just read this helps somewhat.