> then validating and reinforcing their emotions isn’t always helpful

I think you might misintrepet what "validating someone's emotions" is/should do. It's not "You're absolutely right for feeling completely sad and broken down because the cafe wasn't open", but more "That must be such a horrible feeling, to feel so sad and broken down", without saying "yes/no" to if you think it's "justified or not".

The point is that the person is feeling what they're feeling, that's what the validation and acceptance comes in, not about what they're feeling those feelings about.

In the end, you can validate someone's feelings without validating what they're feeling those about, by just saying "that sucks".

I agree with your descriptions of the terms, but I think there's often a divergence between empathy (which I find great) and reflecting people's feelings (which I find good with caution). I want people to understand and help each other. But in some situations, reflecting people's feelings encourages them to make poor decisions. I should always provide a space for people to speak without scorn and with understanding, but I don't want to give a false impression of my concerns. Acknowledging that someone's life sucks is subtly different from acknowledging it aloud, and sometimes the subtlety is crucial.

This is super important. I'd argue that a huge part of learning to process feelings healthily is being and able to tell the difference between how one feels (which is an involuntary reaction that isn't controllable) and the actions taken as a result of that feeling (which require explicit choice to take). It seems obvious in the abstract, but I think it's almost a universal human condition for the line between them to get blurred. People will often say something like "I'm sorry I got mad" as if being angry is something that can be controlled, when what they should instead be apologizing for is the actions they took while mad (e.g. "I'm sorry for yelling"). There's a reason that "anger management" is a known term rather than "anger prevention", after all. If someone asks why you did something, "because I was mad" is not a healthy explanation; it removes your choice from the equation and paints yourself as a helpless victim of your emotions rather than someone with agency and the ability to act better even in the face of extinuating circumstances.

While it might seem like these are just linguistic quibbles, I've seen so many cases of people genuinely thinking that trying to suppress their emotions is the correct way to handle tough situations, and I don't think that ever works well in the long run. At most, it's sometimes beneficial to avoid expressing strong negative emotions immediately in certain situations, but that's only a short term tradeoff to avoid exacerbating whatever is currently going on, not a long term solution to avoid consequences of taking actions under the duress of heavy emotions. I believe that people would learn to act better by mentally framing their emotions separately from their choices and allowing themselves to feel them fully and ideally express them in a healthy way. Venting to a sympathetic family member or friend can be a good way of doing this, but that's also why therapy is something that would be benefit pretty much everyone in my opinion; having a trained, neutral professional to be able to talk through emotions without having to worry about overburdening them or worrying about having to interact with them in any other part of life is hard to beat in terms of a strategy for dealing with tough emotions in a healthy way.

> In the end, you can validate someone's feelings without validating what they're feeling those about, by just saying "that sucks".

If you say "that sucks" the other person is going to assume you're agreeing with them that the thing they're angry about sucks. They're not going to think you're saying "that sucks" that they have an emotion, as an isolated feeling that happened for no reason.

This is where the overly academic concept of "validating emotions without endorsing them" falls apart in the real world.

In actual human interaction, people don't debate if the other person actual feels an emotion. Angry people don't need other people to agree that they feel angry. They share the emotion because they want other people to agree that the emotion is right and justified.

Nobody actually says "I agree that you are feeling that emotion but I neither endorse it nor disagree with it" (in less formal wording). If you're going along with someone else's emotions, you're implicitly endorsing their reaction as justified.