You're human, dear.
We're all finite, at least here and now; there are only so many things we can do, some things just aren't possible to us, and some choices we can make mean other choices cannot be made.... there's always, always that old 'what if?' to keep us less than content.
The question isn't - do you feel a little jealous sometimes when you run across someone who seems to have something you wish you had.
The question is, how do you handle it? Are you mean to them? Snide? Do you hide in the shadows and snipe at them every chance you get, or pounce on any seemingly vulnerable point? Do you gather up some girlfriends and have a putdown party? Do you gush all over them to try to hide your feelings from yourself as well as them? [on edit:] Or do you launch a campaign to discredit them, disparage their work, and keep them from succeeding? These are the things corrosive envy does.
Or do you say, 'dang, girl, I sure envy you, I'd give my eye teeth to do what you've done here,' and grin, and then discover that the one thing she wishes she could do, and never has been able to do to save her soul, is... bake, or write, or... paint - in exactly your medium on exactly your subjects... [on edit:] this is what honest self-acceptance does... it's about facing the things you feel, and letting them be feelings instead of imperatives...
Knowing you, Beth, I'm sure your reaction is in 'dang, girl' country. I do wish we could see your paintings here.
Me, I can't draw to save my life. I have beautiful pictures trapped in my head, and there is where they stay, unless I can paint them with words. The ability to paint for real - to put those pictures on paper, line for line as they are in the mind's eye or the landscape before you - that, I envy.