i have a relative with this problem. they have a close lifelong friendship with someone from a fairly wealthy family. they developed a strong sense of entitlement mixed with envy, which is common for the millenial generation.
none of the entitlement is directed at the friend, however. the entitlement is directed at immediate family members on their side, by expecting various kinds support and family gifts, etc. to afford a spendy lifestyle or live in an affulent area, or by witholding support that they should be giving. everything is manipulated so they have an advantage, basically.
envy is one of the most destructive emotions. one of the cardinal sins.