Jealousy is an emotion that I hate.
Whenever I feel envious of another person, their belongings, their circumstances, I get angry with myself, too, for being ungrateful for all of the wonderful things in my life -- we have a nice house, two cars, a terrific marriage, healthy children and pets, great support through family and friends, and the ability for me to stay at home to raise our kids. That's a huge plus. Sometimes, though, living off of one income just sucks. Sometimes we have to make $100 stretch for two weeks between paydays. Sometimes we have to move what little we have finally been able to put into our savings account back into checking just to get by, and cross our fingers that we don't encounter a serious unexpected expense (ER visit, car trouble, household maintenance needing immediate attention, etc.). While we've never been unable to pay our bills, buy groceries, or put gas in our cars, we just don't have much discretionary income leftover for stuff... that doesn't really matter in the grand scheme of things.
A quote from someone that has stuck with you.