What is the word to use when you don’t know how to feel?
Such as instead of saying:
He didn't know how to feel
You could say
He felt ____.
The perfect word for this comes from today’s slang. In the current vernacular, you would say that he felt meh. It’s recent slang that per Urban Dictionary means
Indifference; to be used when one simply does not care.
For example, from an article on “Five Ways Not to Feel Meh” on Karousing.com:
It’s easy to feel meh. Not up. Not down. Just indifferent. Apethetic. No matter how great life is, we can all fall into the lull of feeling, well, nothing. We get caught up in work, patterns, habits, and fears. I’m here to tell you that there’s a danger to feeling meh. Just like that frog in the pot of water that sits there as the temperature is turned up slowly until it’s boiled to death. Nothing kills your spirit more than the gradual and continuous malaise of feeling meh.
Although some folks might use meh to mean blasé, others use it in a much more neutral fashion.
I immediately thought of the word ambivalent.
- simultaneous and contradictory attitudes or feelings (as attraction and repulsion) toward an object, person, or action
- a. continual fluctuation (as between one thing and its opposite) b. uncertainty as to which approach to follow
A common word for this condition is nonplussed. The link takes you to an online thesaurus for a list of synonyms.
For a common word you could use uncertain or unsure, but depending on if you want to alter the phrase at all, the word vacillate or vacillation would fit perfectly in terms of meaning: "the inability to decide between different opinions or actions" - Oxford Dictionaries.
A selection of other words that mean similar are: ambivalent, irresolute, indeterminate, equivocal.
This is almost a trick question. It implies that people don't just feel emotions, they choose an emotion and slip into it. As though, for example, if I won the lottery and thought.. "ooh what's that emotion I'm supposed to have now ?..erh" and because I can't remember what it is, I never feel happy, I just feel confused. Is that the state you are talking about? You see what I mean?
If you mean he was unable to feel, then perhaps you could say numb.
If you mean that there is an expectation on him to feel a certain way (e.g. when someone dies) and he is not sure how to behave, then I'm not sure that one word will do it.