I think you're absolutely right, inasmuch as resentment builds when deprivation of a desired thing occurs. But I add to it that I also feel that I've been "wronged". It is more than just a feeling of loss. It is a feeling that people should not behave certain ways. This is not pushed on me; I feel that way when something gets stolen from me, or when something gets stolen from someone else. Interestingly, I don't feel it's wrong when I steal. But social conditioning has conditioned me to feel I'm in the wrong when I steal, although in my natural, original state, I don't even bat an eyelash over it. This is why children are normally cruel, (lack of empathy), and lying, cheating, unscrupulous little nips (lack of moral spine): they are in the natural state when they are being able to feel wronged, but they can't cast the domain of this feeling of theirs to being generated by others' misfortunes via empathy.

Then it gets very complicated from there, and basically there could be situations where everyone feels they've been wronged by each other (a closed set of people), such as when war is fought; and some philosophers (Kant, Socrates, Liebliniak, Campiere, D'Inuzzio et cetera) attempted to create systems in which everyone feels there are no wrongs done. Their systems worked theoretically, but not in practice... precisely because morality is developed in the individual via training by society, and most times the training is only partially successful.

But I add to it that I also feel that I've been "wronged". — god must be atheist

But they are not Wrong. You just feel wronged, right?
Edit: You feel wronged, not wrong.

Actually, I did not say They are wrong. I said, "i've been wronged." The two are not the same.

It is incredibly important in philosophy to read texts precisely for what they say, and it is equally important to write precisely what you mean. I think you are good at the second part (your opening post was clear, to the point and without unclear or not reasonable parts; it was well written, logical and reasonable), but you need to work on the first part, and if you are new to philosophy, then it will be an exercise to understand the nuances between subtle differences.

I feel I am doing wrong (not that I'm wrong) in an ethically measured action, when I do something I feel I shouldn't be doing, even though it is to my advantage to do that thing.

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To say "I avoid unethical actions to feel comfortable" is true, but not the whole picture.

They are wrong. I said, "i've been wronged." The two are not the same. — god must be atheist

Yes, I misspoke, I was clarifying that we both agree;

I avoid unethical actions to feel comfortable" — god must be atheist

Super! :100:

One aspect which I think that it is worth clarifying is to what extent you are thinking about the comfort of being protected by morality or about how we are comforted in the form of conscience, personally? Of course, the two interrelate and have probably done so throughout human culture and in all societies. I would imagine that the whole fabric of society is based on this connection of there being certain explicit,or even implicit, rules of some kind.

I do also wonder what you mean by comfort, whether it is about benefits. However, some may see some disadvantages depending on what morality you are speaking of because it covers the whole spectrum of behaviour, ranging from the personal to the social. In this way, it is complex because while most people favour morality of some kind, it is not as everyone agrees on the specifics.

The comfort of belonging comes foremost to my mind, like I mentioned above; if my neighbours feel wronged they will ostracize me and I lose the "comfort" of social interactions.

I think that is the motivational aspect, but apart from that there is a whole process about what is agreed in small groups and in larger groups. In thinking about this, it would probably involve the consideration of the evolution of morality, and probably the whole idea of a social contract, such as Hobbes described.

So what stops us from robbing each other blind? — New2K2

The police and legal punishment do, as well as empathy towards one's neighbour (for those who feel it anyway).

If I rob you, You won't like me, not because of Right or Wrong but simply because I deprived you of something you desire. — New2K2

In my case, I'd say I wouldn't like your action (not you) because you deprived me of something I desire, which makes me feel worse than I otherwise could have felt. And that is precisely what makes your action wrong for me, that is: according to my personal ethics, and not to some universal ethical system.