possessive envy

I hate when I get this way because I know I'm wrong to feel it (and that I'm being selfish). Not only do I know exactly why I'm upset, but I also understand why I shouldn't be. I can acknowledge all the good, see the positive aspects of the other side. I can realize that this is just a matter of ego getting in the way--on a deeper scale, this is nothing. I know that all I have to do is let things be. So why am I still here, feeling this?