Resentment

re-sent-ment |ri'zentment|
noun
bitter indignation at having been treated unfairly : his resentment at being demoted | some people harbor resentments going back many years.
ORIGIN early 17th cent.: from Italian risentimento or French ressentiment, from obsolete French resentir (see resent ).

re-sent |ri'zent|
verb [ trans ]
feel bitterness or indignation at (a circumstance, action, or person) : she resented the fact that I had children.
ORIGIN late 16th cent.: from obsolete French resntir, from re- (expressing intensive force) + sentir 'feel' (from latin sentire). The early sense was [experience (an emotion or sensation),] later [feel deeply,] giving rise to [feel aggrieved by.]

This hurts families, friends and those who are lost to us through such actions. Spending such energy on something like this forces people away and it becomes difficult to get them back. The time away costs future knowledge of ones who they care about. It keeps those who are spending energy on resentment from ever seeing the person for who they are, instead they only see us the way they want to see us. If they want to share the life with loved ones and friends, they will look in the mirror and do some growing up!!!!

No matter the age, time to grow up if you're spending energy on resenting people you care about. Time lost can't be replaced!