I think you are absolutely right that "there's not always a choice in how you feel, but that there is a choice in action. You have many good points, however, your examples highlight subtle but important differences between "offense".

Consider the scorned lover. The nature of his offense is real, in that his spouse transgressed against him i.e. she physically fucked somebody else causing him physical/emotional harm.

Consider the bullied kid. The nature of the threat of violence he has experience is, again, very real as bullying presents the threat of violence/intimidation for the purpose of physical/emotional harm. The point being is that it is a real, identifiable threat.

Now, consider the offended in our original example. Offending ones "beliefs" is effectively a thought crime against the aggrieved, which in and of itself is distinctly unique from the two above examples because it does not present a legitimate threat of physical/emotional harm. I understand how some could argue that offending one's religion constitutes emotional harm, but I disagree as the threat of emotional harm (cheater/bully) in this case is individuated i.e. targeted at individuals for that specific purpose. Whether or not you offend a giant sect of people because you disagree with them and express that in an offensive way in no way, shape, or form constitutes a legitimate physcial/emotional threat. It constitutes a disagreement.

What if rather than sympathizing with the scorned lover for wanting to kill his spouse for actually cheating on him, he wants to kill her because she said she wanted to cheat on him, or maybe made a statement about cheating that fundamentally disagreed with the spouses foundational belief of...monogamy or whatever. Would that warrant sympathy for him in wanting her dead, or, would that be an instance where his position would be justified and tolerated for the sake of inclusion, rather than rightfully calling it a completely disproportionate and unjustified response/perspective.

Further, by extension, what if he was a member of a group of spouses who all supported this idea, and well not all of them acted this way, when one did/does, rather than looking inward and condemning the utter insanity of the position that a guy is justified in murdering his spouse because she said something that offended his belief of how spouses are supposed to behave, the group as a whole (or in this instance a quarter) responded with deflection, "Well...I sympathize with the offended spouse..." or "Well...she should've known he'd respond this way..." or "It's your fault I acted the way I acted when you said the thing that I disagreed with."

It's blame/responsibility shifting rhetoric that removes personal agency from the group responsible for fostering the idea that created the situation in the first place and effectively a non-starter because talking about religion in any logical way is impossible by virtue of the fact that what defines religion is its openness to interpretation.

There are subtle differences, but remember, there is a difference between real threats (bullies and cheating spouses) and ideas (cartoons that offend your belief system), and while I sympathize with scorned lovers and bullied kids, I don't sympathize with people who's feelings are hurt because somebody said something mean about what they think.